Copyright: OMNR Southcentral Science and Information - Significant Wildlife Habitat Decision Support System  Ver. 1.0


Index #1 - Cave Cliff/Migrant Birds/MC/Migratory Route/Stopover Areas
Index #  1

Habitat Type:	Cave/Cliff

Species Group:	Migrant Birds

Significant Wildlife Habitat Category:	Movement Corridor

Functional Habitat:	Migratory Route/Stopover Areas

Habitat Function and Composition

Escarpments provide natural migratory routes for migrating songbirds. Shallow soils and steep relief have allowed these areas to remain natural. Many migrating birds follow cliffs as means of navigating and the cliffs may provide thermal updrafts that aid flight. Small birds stop to feed and rest as they migrate. A diversity of habitat types distributed along escarpments is important in ensuring that migrating birds are able to find sufficient food to sustain energy for migration. The Niagara escarpment provides a continuous band of cover from the Bruce Peninsula to Niagara and is a natural corridor for migrating birds.

The structure and composition of habitats distributed along migration routes are important in maintaining migration functions. A diversity of habitat types ranging from open grasslands to large stands of mature forests offers habitat for a wilde range of migrating bird species having different habitat requirements.

Potential Development Effects

Tree cutting and other lot-clearing activities which reduce foliage density and the number of vegetative layers in forests will affect the quality of habitat for migrating birds. Different species of birds forage at different heights within a forest. Some hunt for food on the ground, others forage in the shrub layer while others glean insects high in the canopy. As vertical structure is lost, fewer species of forest birds are able to forage efficiently in the remaining habitat. Since large numbers of different species of birds concentrate in migration stopover areas it is important that the structural complexity of forests is maintained. Development in a narrow band of the escarpment may bisect the forest cover of the escarpment, isolate habitats, and reduce the function of the area for migrating birds. Development on adjacent land is not expected to affect the function of migration routes provided that buildings do not act as a barrier to movement (e.g. high-rise office towers may cause considerable mortality of migrating birds).

Mitigation

Development should be planned so that construction and related human activity is concentrated in as small an area as possible. Large areas of continuous forest cover should be avoided or if used, should only be developed at the edge rather than in the interior. If forest habitat will be affected, the forest/woodland habitat indices should be referred to.

Basic principles for retaining the functions of migration corridors are:

1) 	minimize the amount of loss and disruption of forest cover (i.e. cluster development where possible);

2) 	ensure that development does not completely sever migration corridors; and

1)	ensure that each area retains a good variety of habitat types.


Index #2 - Cave Cliff/Bats/SCA/Hibernacula
Index #  2

Habitat Type:	Cave/Cliff

Species Group:	Bats - little brown myotis (or little brown bat), northern long-earedbat, eastern small footed bat, eastern pipistrelle, silver-haired bat, big brown bat

Significant Wildlife Habitat Category:	Seasonal Concentration Areas

Functional Habitat:	Hibernacula

Habitat Function and Composition

The bats of Ontario are insectivores and cannot find enough food during cold weather when insect activity ceases. Some bats migrate south to avoid the food-limited winter months while others stay behind and hibernate. Hibernating bats seek out caves or other similar structures which provide protection from freezing temperatures and predators. Caves, abandoned mines, and crevices provide safe and undisturbed hibernation sites from early autumn to mid spring when flying insects are inactive. Ideal hibernacula are few, and bats will migrate long distances from vast areas to hibernate in a particular cave.

To function as a hibernaculum, caves and other sites need to have substantial roosting areas. Active sites usually have a series of chambers linked by tunnels which are large enough for bats to fly through. Protection is provided by a restriction in the tunnel so that air exchange, temperature and humidity remain moderated and relatively constant in the roosting area. Ideally caves should be five times longer or deeper than they are wide at the openings. Overhangs and big open-mouthed caves are not suitable. The more complex and deep the cave system is, the more likely it will function as a hibernation site. Streams and water flow help to moderate temperature and moisture inside the cave. Remote access and restricted openings to the caves help to prevent disturbance from other competitive or predatory species. Bats are very intolerant of any disturbance during hibernation.

Potential Development Effects

Development should not affect bat hibernacula unless site alterations are planned for the cliff face or abandoned mine itself or if they affect groundwater flow. Site alterations which result in the loss of vegetation within 200 m of entrances to hibernacula carry with them the risk that bats will abandon the site. Since suitable hibernation sites are limited, the loss of any site has significant impacts on bat populations.

Excavation is the site alteration which presents the greatest potential for impacting bat hibernacula. If cliff faces are excavated (or built on) there is a risk that bat hibernacula will be destroyed. Excavation and construction on the top margin of cliffs and associated tablelands which alter groundwater flow may affect the function of caves and mines as bat hibernacula. If caves become dry as a result of changes to groundwater flow then the site may no longer be suitable as a hibernaculum. Bats which are forced to use dried-out sites may be prone to higher mortality than normal.

Development near bat hibernacula may result in human disturbance. Excessive disturbance may result in high winter mortality and eventual abandonment of the site.

Mitigation

Development should be directed away from cave openings and other hibernacula. A setback distance of 200 m from openings to hibernacula is suggested. Each site is likely to have unique characteristics which should be considered when determining appropriate setbacks in an Impact Assessment. If human activity is likely to increase in the area as a result of the development, then steps should be taken to prevent human access to caves. Bars and other metal grids have been used successfully to protect bat caves from human disturbance. Some protective forest cover should be retained leading to the cave to facilitate the movement of bats to and from hibernacula. If development is planned in groundwater recharge areas above the hibernacula, hydrogeological studies should be completed to demonstrate that moisture regimes within the hibernacula will not be adversely affected.


Index #3 - Cave Cliff/Cliff Nesting Birds/RSH/Nesting Sites
Index #  3

Habitat Type:	Cave/Cliff

Species Group:	Cliff-Nesting Birds: Turkey Vulture, Peregrine Falcon [ENDANGERED], Common Raven

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat: 	Nesting Sites

Habitat Function and Composition

Cliffs provide unique and specialized nesting sites for these birds. The isolation of a cliff ledge reduces the potential for nest predation. The nesting site may be under the protection of an overhang or exposed to the elements. Established nest sites may be used for decades through several generations. Traditional sites have unique microhabitat characteristics that are keyed into by successive generations of birds. These may include factors such as updrafts, drainage of the nest site, and exposure to the sun, which varies depending upon which way the cliff faces. Some PeregrineFalcon nest sites have been occupied for centuries.

Cliff-nesting sites are most often situated on a remote and protected section of the cliff. Nests are typically built where there is good drainage to prevent precipitation or melt water from flowing onto the nest. Exposure to direct sun is often avoided by selecting sites that include a variety of shade and sun throughout the day. Shading may add to the camouflage and help to conceal the nest during incubation and nestling stages. Dimensions of the site will vary depending on the species using it as a nest site, but usually a minimum of about 1 m x 1 m is required.

The Turkey Vulture rarely nests on cliffs, but occasionally uses caves for nesting. Darkness appears to be an important factor in nest-site selection, where optimal caves are deep enough to allow only minimal light to penetrate to the nest site.

The Peregrine Falcon is an endangered species in Ontario. Therefore, no development is allowed in the significant portions of its habitat (Natural Heritage Policy). Important habitat components are the nest site and nearby large water bodies. Nests are typically depressions on cliff ledges with good drainage, usually with shallow gravel in which a scrape can be made and with some vegetation such as grasses or a stunted tree. Ledges selected for nesting have little to no overhang, and most Ontario nests face east or north to avoid the afternoon sun. Most territories contain several nest sites, and pairs often use alternate nest sites in subsequent years. Alternate nest sites may be as far as 6 km apart. Therefore, the absence of nesting birds on a ledge one year does not necessarily mean that it is not critical habitat.

Away from urban areas, Peregrine Falcons feed primarily on birds, particularly waterfowl and shorebirds. Lakes and large rivers with extensive littoral habitat and open shorelines are favoured hunting areas. Critical feeding areas may be as far as 20 to 27 km from the nest.

The raven is not an obligate cliff nester, frequently nesting in trees or on manmade structures. Most nest sites overlook open vistas and a high proportion of them are near water. Most cliff ledges used by ravens in Ontario face southwest.

Potential Development Effects

Development has the potential to disrupt the function of a cliff face or cave as nesting habitat whether site alterations occur on the cliff itself or on adjacent land. Any construction, tree cutting, excavation, or increase in human activity on the cliff face or on adjacent lands may cause birds to abandon the area for nesting. Nesting birds tend to be highly intolerant of disturbance. Individual birds react differently to human disturbance. Some Peregrine Falcons nest within cities and are apparently oblivious to disturbance. Birds accustomed to nesting in isolated areas tend to be very intolerant of human activity. We suggest a 1 km setback from traditional cliff-nesting sites for the Peregrine Falcon and 500 m for the Common Raven to be conservative and to ensure that the nesting birds are unlikely to be disturbed. In Illinois, no Turkey Vulture nests were within 80 m of an active dwelling. A setback of 200 m from an existing nest site is suggested for new development. Proponents may be able to conduct site-specific studies to demonstrate that development closer than this will not have negative impacts.

Ravens prefer extensively forested areas. Large-scale developments which reduce the amount of forest cover may cause ravens to abandon the area even if nest sites are not affected.

Development on top of hills where nesting ledges or caves occur has the potential to change drainage patterns at the nest site.

Development on adjacent land which reduces the availability of food for nesting birds will affect their ability to raise broods successfully. If foraging efficiency is greatly reduced brood rearing success may become very low. This affects local population dynamics and long-term persistence of populations.

Mitigation

Mitigating the effect of development on cliff-nesting and cave-nesting birds may not be possible. The fact  that these birds select such remote sites for nesting in the first place indicates a low tolerance to disturbance. Any increase in human activity in the vicinity of nests may result in nest abandonment. Avoidance of cliff nest sites is the optimum mitigation technique, particularly for the Peregrine Falcon.

Any development proposals that may affect Peregrine Falcon nest sites or feeding habitat will require input from the Ministry of Natural Resources and the Canadian Wildlife Service.


Index #4 - Cave Cliff/Woodland/Forest/Reptiles/SCA/Hibernacula
Index #  4

Habitat Type: 	Cave/Cliff; Woodland/Forest

Species Group: 	Reptiles: eastern garter snake, red-sided garter snake, redbelly snake, brown snake, blue racer [ENDANGERED], smooth green snake, northern ring-necked snake, eastern hognose snake [VULNERABLE], black rat snake [THREATENED], milk snake, eastern massasauga [THREATENED], timber rattlesnake [ENDANGERED]

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Hibernacula

Habitat Function and Composition

Many snake species move to wooded areas or areas associated with cliffs during the autumn and select protected areas to hibernate. Some species may concentrate in numbers in a few sites distributed throughout the forest or along the base of a cliff. Snakes often select sites with an abundance of dead organic materials such as tree stumps or logs that have fallen and are decaying. The decaying process produces a small amount of heat which the reptiles take advantage of. Hibernation also takes place in sites located below frost lines in burrows, rock crevices and other natural locations. Snakes depend on these types of sites to escape freezing temperatures. An abundance of sites are needed to ensure overwinter survival. The accumulation of rock and wood at the base of cliffs provides crevices and other structures needed for hibernation. Areas of broken and fissured rock are particularly valuable since they provide access to subterranean sites below the frost line. Some species (garter snake, black rat snake) may hibernate in large numbers at a site while others are more solitary. Typically snakes emerge on warm sunny days in the spring, bask in the sun on surrounding rocks to overcome the physiological effects of hibernation, and retreat to the hibernacula at night when temperatures are below freezing. After a few days or weeks, they begin to disperse to the summer range.

Large woodlands (>30 ha) with an interior of mature forest generally provide more suitable conditions for hibernacula than small, narrow woodlands. This is particularly true for some of the larger snakes. The climate in interior forest areas tends to be more moderate than in open areas or at the forest edge.

Potential Development Effects

Development may affect a number of hibernacula or the effectiveness of hibernacula if it involves the area of accumulated rock and woody debris at the base of cliffs, significantly reduces forest size, or removes logs and other debris on the forest floor.

Lot clearing, excavation, construction and road building activities present considerable risk to hibernating snakes. These activities can result in direct mortality to snakes. Even development in the adjacent lands can result in mortality as large numbers of snakes (in some cases) try to move to the hibernacula. As the forest canopy is opened up, the microclimate of the forest interior becomes more variable. If this results in extreme temperature fluctuations within hibernacula, overwinter survival may be reduced. The effects of these habitat changes may only be realized in the most severe winters. From a population standpoint, the effect can be devastating, with large-scale winter mortality eliminating any accumulation in numbers in a single season.

Excavation, road building and construction can easily destroy quality hibernacula by preventing access to subterranean resting sites.  These activities may also permanently remove active sites from the area. Loss of these habitat features usually goes undetected since it is very difficult to recognize hibernacula using ground surface cues and since reptiles themselves tend to be secretive.

When hibernation sites are lost in an area, snakes are forced to select alternate sites. Many such sites will not provide sufficient protection from the extremes of winter weather or there may be no nearby suitable hibernacula. Reptiles which find themselves in marginal sites for the winter are at risk of winter mortality and susceptible to predation. If the majority of quality hibernacula are eliminated there can be serious impacts on reptile populations and their long-term persistence.

Construction and site alterations which reduce the size of forest or alter the habitat, may make the area less suitable for prey such as small mammals and amphibians. If prey are reduced too much, the carrying capacity for reptiles may decline.

Development on adjacent lands is not expected to affect the function of hibernacula. However, road construction near hibernacula may increase reptile mortality. As reptiles migrate to hibernacula they often rest on roadways taking advantage of the heat road surfaces provide. Many may be killed by cars. Increased road mortality can affect the viability of small isolated populations.  Also, large-scale developments which sever habitat linking summer range and hibernacula will prevent many snakes from reaching traditional winter areas. Development may eliminate or reduce habitat critical in other seasons, or interrupt migration routes. Many humans have an aversion to snakes. Larger snakes are highly likely to be intentionally killed by people, but even small, harmless snakes may be at risk. As the number of people increases so does the likelihood of people-snake interactions, and many snakes may be destroyed. Subsequent lot clearing and landscaping can further degrade the habitat.

Mitigation

If development is to occur in a woodland area providing reptile hibernacula or in accumulated broken rock and fallen timber at the base of cliffs, then mitigation will involve protecting the forest canopy and amount of downed woody debris and rocks. Restriction of the amount of excavation and filling that can occur and restrictions applied to roadways and provisions to direct activity away from openings to underground resting sites may be required.

Steps should be taken to control speed on roads in the vicinity of hibernacula. Signage and public education programs may help to prevent excessive road mortality and mortality at the hands of humans. In some cases, underpasses, culverts, or tunnels for snakes may be effective.

There may also be opportunities to construct snake hibernacula. This may be accomplished by excavating a hole that extends below the frost line and filling it with rocks. Artificial hibernacula should be carefully designed to ensure that they do not fill up with water and become an ecological trap for snakes that use them. If this is recommended as a mitigation technique to offset loss of existing snake wintering habitat, it should be installed and be demonstrated that it is a functional hibernaculum before development proceeds.

Hibernacula are difficult to find and few are identified. During the planning process, inventories of the site should be conducted specifically to locate potential hibernacula. If species like the blue racer, eastern massasauga, hognose snake, or black rat snake are found, the most likely locations of hibernacula should be noted. These areas can be checked in spring to confirm use. Active sites should be protected along with a suitable amount of habitat for the species in question. It must be recognized that, like deer yards, hibernacula are very important habitat. Individuals from a large surrounding area depend on a small number of hibernacula for their survival.

Two of the snakes in this guild are protected under the Ontario Endangered Species Act: blue racer and timber rattlesnake. Any development that may involve these species will require consultation with the Ministry of Natural Resources. This is unlikely to be a problem in most cases. The blue racer appears to be restricted to Pelee Island and the timber rattlesnake has probably been extirpated from the province. The eastern massasauga and black rat snake are threatened in Ontario and development is not permitted in the significant portions of their habitat (Natural Heritage Policy). These species are more widespread and more likely to be affected by development proposals.


Index #5 - Cave/Cliff/Turkey Vulture/Seasonal Concentration Area/Summer Roosting Areas
Index #  5

Habitat Type: 	Cave/Cliff

Species Group:  	Turkey Vulture

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat:	 	 	Summer Roosting Areas

Habitat Function and Composition

During summer Turkey Vultures seek out secluded areas of cliff faces to use as roost sites. Manmade cliffs such as quarries and gravel pits may also function as vulture roosting habitat. Large numbers of vultures (adults and newly-fledged young) may concentrate in suitable areas. These roosts are used primarily for loafing and sun-bathing. Sun-bathing is very important to vultures as it helps to regulate body temperatures and is essential if the feathers have become wet due to rain. During periods of heavy or prolonged rain Turkey Vultures are unable to fly and require areas where they can quickly dry out and resume foraging. Cliffs also enable vultures to become airborne quickly. Preferred cliff-roosting sites should be relatively free of vegetation to provide maximum exposure to the sun and no obstructions to flight. Vultures will often also roost in trees at the tops of cliffs or hills.

Potential Development Effects

Development near cliffs acting as summer roost sites may disrupt the function of the cliff as a roost due to human disturbance. Vultures select these areas to avoid disturbance by humans and predators and for the microhabitat features that they provide.

Development affecting the cliff face or edge may have the greatest impact on vultures. Loss of tree cover (where vultures roost in trees) or regrading to reduce the slope of cliffs will have the greatest impact on the quality of the site for summer roosting. Increases in human activity in the vicinity of the site may lead to abandonment of the site.

The distance threshold at which roosting vultures may be unduly disturbed is uncertain. Some known roosts are within 200 m of rural housing, but it is unlikely that vultures would tolerate subdivisions this close. The height of the cliff may also affect vulture tolerance of human activity. Roosts on low cliffs are more likely to be affected than those that are a considerable distance above the development. It is suggested that development not occur within 500 m of a summer Turkey Vulture roost unless site-specific studies indicate that birds will tolerate development closer. The required setback may be dependent on the intensity of development and perhaps the remoteness of the site. A single house may be tolerated very close to a roost. On the other hand, a large development within 500 m is unlikely to be tolerated by the birds. Roosts in remote areas are more likely to be abandoned than those in areas where human activity is common.

Mitigation

It may not be possible to mitigate the effects of development on summer roost sites of Turkey Vultures since these birds select remote sites owing to their relatively low tolerance of human disturbance. Sites are also selected for their habitat characteristics such as flight path and exposure to the sun.

The optimum mitigation is to avoid development within the vicinity of vulture roosts. Where the roost is on the face of an abandoned gravel pit, the slope of the face should not be decreased.

When large-scale development is planned near a vulture roost, even outside of the suggested 500 m buffer, steps should be implemented to minimize or eliminate human usage of the area. There are several techniques that may be effective in accomplishing this, but the onus will be on the proponent to demonstrate that human intrusion can be controlled.


Index #6 - Field/Meadow Habitat/Grassland/Shrubland Birds/Habitat of Species of Conservation Concern/Breeding Habitat
Index #  6

Habitat Type: 	Field/Meadow Habitat

Species Group: 	Grassland/Shrubland Birds: Northern Harrier, Northern Bobwhite [ENDANGERED], Upland Sandpiper, Short-eared Owl [VULNERABLE], Loggerhead Shrike [ENDANGERED], Yellow-breasted Chat [VULNERABLE], Prairie Warbler [VULNERABLE], Dickcissel, Lark Sparrow, Henslow’s Sparrow [ENDANGERED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Breeding Habitat

Habitat Function and Composition

A number of Ontario’s birds require areas of relatively large open grasslands or shrublands. Other species nesting in these habitats may not require extensive areas, but have very specific habitat requirements which limit their distribution. For these species, grasslands and shrubby areas provide essential food, cover and nesting habitat.

The primary requirements of these open country birds is highly variable, but they represent an open-habitat guild. The following table outlines the general habitat requirements of grassland and shrubland birds of conservation concern:

Species	Habitat Characteristics
Northern Harrier	Prefers large, open fields with minimal shrub or tree coverage; seems to prefer open areas that are 30 ha in area or larger, but occasionally nests in smaller habitat patches; also nests in marshes, bogs, and fens; in fields, grass cover taller than 50 cm is preferred and the nest is often situated on a small knoll
Northern Bobwhite	Requires grassy areas for nesting, shrubby areas for escape cover, and croplands for feeding; optimum areas have about 50% bare soils, with remaining areas containing upright herbs and shrubs; optimum habitat mix appears to be 30 to 40% grassland in 2- to 4-ha parcels, 40 to 60% cropland in 0.4- to 2-ha parcels, 5 to 20% shrubland in 0.1- to 0.4- ha parcels, 5 to 40% cropland in 2- to 8-ha parcels; avoids the interior of forests, large fields or prairies; very sedentary, often spending its entire lifetime within an area of 50 ha
Upland Sandpiper	Nests in old fields, hayfields, pastures, and at airports; may have originally been associated with short-grass prairie, also occurs on alvars; appears to require about 25 ha of open habitat; prefers uniform grass cover 15 to 30 cm in height, avoids areas where grass height exceeds 60 cm; presence of residual vegetation from previous years is important; needs perches for displaying such as fenceposts
Short-eared Owl	Prefers grasslands of various heights, densities and species composition; also nests in bogs, fens, and marshes and on extensive sand dunes; appears to require about 75 to 100 ha of contiguous open habitat; nests tend to be in grass 30 to 50 cm tall, occasionally in vegetation as tall as 1 m; nests are often on knolls elevated 1 or 2 m above the remainder of the field
Loggerhead Shrike	Requires open fields of short grass and herbaceous plants with scattered shrubs or small trees (hawthorn or red cedar); scattered trees are used for nesting, perching, and impaling prey; uses marginal farmland, lightly-grazed pastures, and alvars; nearby wetland habitat may be important; probably needs at least 25 ha of suitable habitat
Prairie Warbler	Prefers dry fields or rocky barrens with abundant shrubby vegetation; pine/oak/juniper shrublands are often used as are extensive sand dunes; common juniper is the preferred nesting cover
Yellow-breasted Chat	Prefers old fields with a relatively high density of deciduous shrubs and saplings; very dense areas overgrown with shrubs and vines are preferred
Dickcissel	May have originally been associated with tallgrass prairie; nests in clover and alfalfa hayfields, undisturbed grasslands, old fields, and pastures; prefers heavily-vegetated fields with tall grass and herbaceous plants at least 50 cm tall; needs taller herbaceous vegetation or scattered trees and shrubs for singing and perching; dense litter 5 to 8 cm deep is preferred; will nest in habitats as small as 1 to 10 ha
Lark Sparrow	Prefers disturbed, open fields with short vegetation (? 15 cm), and large amounts of bare ground with scattered boulders, trees, or shrubs that can be used as singing perches; often found in association with sandy soils and pine barrens; needs a minimum of 10 ha of suitable habitat
Henslow’s Sparrow	Originally associated with tall-grass prairie; nests in heavily-vegetated fields dominated by grasses; prefers grass 1 m tall or more, but will use areas where grass is a short as 25 cm; tends to avoid fields where shrub coverage is much greater than 1%; tall, sturdy, herbaceous vegetation stalks are necessary for perching (common mullein, evening-primrose); low-lying (moist) fallow fields with an accumulation of dead plant material provide the highest quality habitat; long-term populations are associated with fields 40 ha in area or larger
Potential Development Effects

Grassland and shrubland species are at high risk because the habitat that they depend on is generally considered wasteland with limited ecological value. These habitats are often considered prime development areas, and they are frequently planted to trees. Most of these species are experiencing declines. Many other grassland birds that have declining populations were not included in this index because they are still common in the province. Unless  trends change, it is likely that additional species of concern will be added to this index.

Development which affects habitat supporting any of these bird species will affect the use of this significant wildlife habitat. Some of the species within this guild are threatened or endangered in Ontario: Northern Bobwhite, Loggerhead Shrike, Henslow's Sparrow. Development is not permitted within the significant portions of the habitat of these species (Natural Heritage Policy 2.3). The Ministry of Natural Resources must be consulted for any development proposal that may affect these species. Other species in this guild are considered vulnerable in the province, and the guidelines for the PPS suggest that, at a minimum, the best examples of habitat for vulnerable species should be maintained.

Excavation or construction which reduces the amount of suitable habitat will affect the number of birds which can use the field for breeding. Most birds are territorial during the nesting season and must retain a large enough area to forage and provide for their offspring.  Reductions in the area of field will result in the loss of nesting territories or a reduction in the amount of food available to birds. The net result is a reduction in brood success. Loss of suitable habitat is particularly critical to area-sensitive species that require a large patch of suitable habitat. Decreasing the amount of grassland habitat below a species' threshold size may result in its abandoning the area. For example, reducing the area of a grassland from 150 ha to 50 ha will reduce the number of breeding pairs of species that are not particularly area sensitive, but may result in the loss of breeding Short-eared Owls.

Site alterations which change the composition or structure of grasslands (i.e. establishing lawns, etc.) or which result in the conversion of open areas to forest (i.e. tree planting or prevention of fire or grazing which once kept the area open) will have negative impacts on grassland birds. The above table demonstrates that many of these species have very specific microhabitat requirements; any changes in these will be detrimental.

Residential developments which result in there being many free-ranging pets (cats and dogs) will affect nest success by introducing significant predation to the area. Cats are significant competitors for prey for species such as Northern Harrier, Short-eared Owl, and Loggerhead Shrike. Shrikes are often killed on roads.

The two raptor species in this guild are susceptible to human disturbance. Human incursion into the nesting habitat may result in nest abandonment, or predators may follow human trails to find nests.

The Northern Bobwhite is particularly at risk because it requires several different habitat types in close proximity and it is very sedentary. Thus, the loss of any critical habitat component may result in the extirpation of a local population.

The Loggerhead Shrike is also at high risk because it often relies on lightly-grazed fields for nesting and hunting. By simply removing cattle from shrike habitat, the area may no longer be viable habitat.

Many of the species in this group nest on the ground and have very specific soil moisture requirements. Development which results in fields becoming drier or wetter may result in abandonment of the area by the species of concern.

Mitigation

Development should not reduce the amount of suitable habitat below the threshold size required by any area-sensitive species that occur in the area. Generally, if the amount of habitat that remains is large enough to support the most sensitive species, all other species should be protected.   Therefore, a good inventory of the species that are using a particular site is very important.

The area left should be in one large patch rather than broken up with large rural lots where they have included the large lots as part of the total grassland habitat. Patch shape is also important, much the same as for interior forest. Clustering development may reduce the amount of habitat that is affected.

Impact Assessments should address drainage, habitat structure, and human and pet usage. Stormwater management studies and, in some cases, hydrogeological studies, will be required to determine if changes in grassland moisture regimes will occur. If changes may occur, then impacts on vegetation composition and structure should be determined along with ramifications on significant grassland and shrubland species. Species that require tall, thick grasses such as the Dickcissel and Henslow’s Sparrow are especially vulnerable to a site becoming drier.

Even if drainage patterns and most of the grassland/shrubland is maintained, management (or lack of intervention) may be required. Landowners may consider an adjacent old field to be a weedy eyesore. The temptation to plant trees or mowing must be averted. Interpretational signs or other educational techniques should be employed so that residents understand that they are living adjacent to significant species habitat and species. However, the reality is that interpretation often does not work.


Index #7 - Field/Meadow Habitat/Insects/Habitat of Species of Conservation Concern/Breeding Habitat
Index #  7

Habitat Type: 	Field/Meadow Habitat

Species Group:  	Insects: monarch butterfly [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Breeding Habitat

Habitat Function and Composition

Though abundant in Ontario, the monarch butterfly is a species of conservation concern owing to its vulnerability on wintering habitat in the southern United States and Mexico. Butterflies raised in Ontario migrate each autumn to distant southern winter ranges. Adults leave the winter range in spring and breed and die shortly afterwards. Subsequent generations migrate, breed and die, resulting in the arrival of new adult butterflies in Ontario by summer. The continued existence of monarchs depends on the conservation of its larval host plant, milkweeds. Large autumn migrating populations are required to ensure survival of adequate numbers on the winter range to begin the migration process each year.

For a field or meadow to function as breeding habitat for monarch butterflies, it must contain relatively large populations of milkweed plants. Monarch caterpillars feed almost exclusively on these plants. The most important host plant is the common milkweed, although the swamp milkweed may be locally important in damp meadows and at the edge of marshes. In prairie-like habitat, the butterfly weed is used as a host. There are several other native species of milkweeds, but most are either too rare or occur in forested habitat so that they are not important to monarchs. Non-native milkweeds, such as the dog-strangling vine, may also be used. Rarely, it may use spreading dogbane and indian hemp.

Fields and meadows provide habitat for a variety of butterflies. Some are permanent residents overwintering as pupae while others are migratory. The key to ensuring the persistence of viable butterfly populations is the maintenance of diverse plant communities. Habitat maintained for monarch butterflies will benefit many butterfly species.

Potential Development Effects

Since milkweed plants often thrive in human-altered landscapes, development may not always have negative impacts on monarch butterfly breeding habitat. Subdivisions which result in extensive paving, building, lot clearing, and weed control will reduce the function of open meadows as breeding habitat. Areas most at risk are those with extensive populations of milkweeds; the loss of areas with scattered milkweeds should not have a negative impact on the species' population.

Development on land adjacent to meadows with abundant milkweed populations will only affect monarch breeding habitat if it results in the application of weed control measures in the meadow. One problem is that the common milkweed is considered a noxious weed under the Weeds Act. In developing areas, particularly if they are near agricultural land, there may be a requirement to eradicate milkweeds.

Another problem is that habitat for monarch butterflies is rarely identified as significant wildlife habitat. Critical monarch butterfly habitat areas are often passed off as weedy areas having no natural values.

Mitigation

Mitigating the effects of development on monarch butterfly breeding habitat involves making provisions for the development and maintenance of milkweed populations. This may require significant changes in the public perception of milkweed as an undesirable and invasive plant species. Many urban areas are promoting the concept of naturalized areas. Naturalized areas provide a diversity of flowers and “weeds” which provide habitat for many species of birds, small mammals, and insects. Subdivisions should be planned so that some naturalized areas are left or butterfly gardens could be established within the development. Incorporation of naturalized areas within or adjacent to development is often a valuable asset to the community; they also function as interpretive and recreational areas.


Index #8 - Field/Meadow/Raptors/Rare or Specialized Habitat/Hunting Areas
Index #  8

Habitat Type:	Field/Meadow

Species Group: 	Raptors: Northern Harrier, Red-tailed Hawk, Rough-legged Hawk, American Kestrel, Merlin, Barn Owl [THREATENED], Eastern Screech-Owl, Great Horned Owl, Snowy Owl, Long-eared Owl, Short-eared Owl [VULNERABLE]

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat: 	Hunting Areas

Habitat Function and Composition

Fields and open meadows provide vital hunting areas for a variety of raptors. As a group, these birds take advantage of open areas where prey is exposed and most abundant. Open areas provide good visibility and unimpeded flight for successful hunting. Relatively large and productive populations of small mammals as well as ground nesting birds (e.g. sparrows) can be found in field/meadow habitats. These habitats provide the biomass of prey required by top carnivores like raptors to survive and reproduce. The persistence of local populations is highly influenced by food supplies. Fields and meadows are key features of the habitat of many raptor species. Some species like the Northern Harrier and Short-eared Owl nest in this habitat.

For fields and meadows to function as hunting areas they must provide suitable habitat for prey species. A diversity of herbaceous plant species offering a mix of green leafy plant matter, seeds, nuts and fruits throughout the year will provide conditions for maximum prey density and productivity. Areas with grasses or forbs 5 to 30 cm in height are ideal, as this provides adequate cover for small mammals, yet the cover is not so dense that raptors cannot detect prey. Airports and road rights-of-way often provide good foraging habitat for raptors. Additional habitat features of the area will often include fencerows and other structures to provide dispersal routes for animals migrating to and from the area. Immigration of small mammals is important for sustaining viable prey populations and to dampen population fluctuations in local habitats subject to relatively high mortality rates. Adequate hiding cover is needed to ensure that predators do not exert too much pressure on prey populations causing them to decline to low levels no longer providing sufficient food for raptors (Note: a number of reptilian and mammalian predators will also be foraging on prey located in field/meadow habitat).

Standing dead timber or other vertical structures distributed throughout the open area may be used as perches by raptors. From these vantage points raptors can rest and conserve energy while searching for prey.

Habitat size is important for the Northern Harrier and Short-eared Owl. Unlike the other raptors, which hunt from a perch, they do most of their hunting by coursing low over a field or meadow. They seldom hunt in fields smaller than 10 ha, and prefer larger areas.

Potential Development Effects

Development occurring in field/meadow habitat will affect the function of the area as hunting/foraging sites by a variety of raptors. Development which increases human activity may result in the abandonment of the area by hawks. Abandonment by raptors is most likely if site alterations change the composition and structure of the field vegetation. Mowing and other lot-clearing activities which cause the existing plant community to be replaced with a less diverse and structurally complex community will not produce the high-density small mammal populations that attract raptors. Tree removal will reduce perches. Development may reduce the size of the feeding area to the point where it is no longer effective to hunt in it, or field size may be reduced below the threshold size required by Northern harriers and Short-eared Owls.

Development on adjacent land is not expected to impact raptor hunting areas directly. However, if human activity increases in fields and meadows near the development, then birds may abandon the area. Pets such as cats can reduce prey populations to the point where it is no longer effective for foraging.

Mitigation

It may not be possible to mitigate the effects of development in field/meadow habitat functioning as a raptor hunting area if increases in human activity are expected. Birds will abandon the site  due to disturbance effects making the habitat ineffective as a foraging area.

If human activity is not expected to increase in the area, then steps should be taken to ensure that existing plant communities are not affected. The key is to keep the remaining area as attractive to small mammal populations as possible. This requires a diverse plant community and a structurally complex ground layer. In some instances the loss of field area can be compensated by improvements to the remaining plant community to increase its diversity. Hiding cover and linkages between different areas of the field and nearby fields can be constructed to enhance the habitat for small mammal populations.

Attempts should be made to prevent fields from being greatly reduced in size. This may involve clustering development in margins of open areas. If field size is reduced raptors may abandon the feeding site.

Where suitable perches are limited, artificial perches are often successful in increasing raptor numbers.


Index #9 - Field/Meadow Habitat/Amphibians/Seasonal Concentration Area/Summer Habitat
Index #  9

Habitat Type: 	Field/Meadow Habitat

Species Group:  	Amphibians: leopard frog, pickerel frog

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Summer Habitat

Habitat Function and Composition

During the summer leopard and pickerel frogs move from ponds, marshes, and other wetlands to wet meadows. They do this to take advantage of the abundant supplies of insects produced in these habitats. Large concentrations can be found in some areas. Areas of intense frog activity are often highly localized, being centred on the most moist areas of larger field/meadow habitat. Although these species will migrate a considerable distance from wetlands most select summer habitats located within 100 m of standing water.

Open grassy areas with poorly-drained soils provide conditions moist enough to function as summer habitat for these frogs. Grasses, sedges and rushes are common plants in areas inhabited by leopard frogs. Patches of shrubs and trees provide shade and cool, moist microclimates which serve as daytime resting areas. An abundance of downed woody debris and other structures that frogs can get under during dry spells enhances the quality of the area as summer range.

Potential Development Effects

Large-scale developments have the greatest potential to affect areas of leopard and pickerel frog summer range simply because of the expansive areas involved and major changes that are made to the hydrological function of the area.

Excavation and drainage associated with development are usually undertaken to dry the site and direct surface water away from buildings, roads and other structures. Any permanent drying of soils within open meadows will disrupt the function of the area as summer range for frogs.

Lot-clearing activities are another source of impact on frog habitat. As wild grassland plant communities are mowed and replaced with manicured lawns, etc. their suitability as insect-producing areas is reduced. Cleared or mowed sites also tend to dry out more quickly than naturally-vegetated areas. The increased frog mortality rate associated with lawn cutting in rural areas should not be discounted as to its effect on local frog populations. Removal of downed woody debris reduces the availability of daytime resting sites for frogs and other species. The net effect of these activities is a drying of the area which results in its loss of function as summer habitat.

Development on adjacent land may affect summer frog habitat if changes to hydrological function occur. If any parts of the development prevent frogs from moving from the wetland to moist meadow habitat then areas of summer range will become devoid of frogs. Increased traffic may result in increased mortality of frogs crossing roads.

Mitigation

It may not be possible to mitigate the effects of multi-lot development on leopard and pickerel frog summer habitat if large-scale changes to the area's moisture regime occur. If hydrological function can be retained to maintain areas of poorly-drained soils, then summer frog habitat could be protected provided that vegetation is unaffected and habitat corridors are left to link summer habitat to nearby wetlands.

In some situations it may be possible to excavate depressions which will collect surface water. If natural vegetation is allowed to grow wild on drainage ponds and a supply of downed woody debris is provided, these sites may be used by frogs during summer (provided there is a linking corridor to adjacent wetlands). Each wetland should have easily-accessible summer habitat. If existing summer habitat can not be preserved then it may be possible to create new habitat. Habitat areas must be large enough to prevent the concentration of large numbers of frogs in small areas. Such a dispersion pattern would make frogs vulnerable to predation. Proponents should demonstrate that newly-constructed habitat is being used by amphibians.

Development should be designed so that the wetland and an area of adjacent land that can be used by frogs are protected.


Index #10 - Field/Meadow/Raptors/Seasonal Concentration Area/Winter Roosting Areas
Index # 10

Habitat Type:	Field/Meadow

Species Group: 	Raptors: Northern Harrier, Short-eared Owl [VULNERABLE]

Significant Wildlife Habitat Category:	Seasonal Concentration Area

Functional Habitat: 	Winter Roosting Areas

Habitat Function and Composition

Hay fields, pastures and open meadows provide critical winter roosting areas for Northern Harriers and Short-eared Owls in southern Ontario. Sites with key habitat components may attract large numbers of roosting birds, and the two species may occasionally roost together. Sites may be traditional, being used by birds year after year.

These two raptors roost on the ground in winter. Good roosting habitat consists of large enough fields (usually >20 ha) so that they are not disturbed, adequate cover and appropriately-coloured vegetation to camouflage the birds, and a nearby source of prey, which is typically meadow voles.

Ideal harrier roosts are large stubble fields overgrown with weeds. Initially, roosts may be small and situated in low-lying areas near the hunting grounds. As snow depth increases, birds tend to concentrate in higher areas with less snow cover.

Short-eared Owls usually roost in fields in winter, but they have also been documented roosting in marshes, quarries, and gravel pits. As many as 200 birds have been counted in some roosts in the States, with as many as 50 documented in some southern Ontario roosts. Light-coloured vegetation that matches its plumage is preferred, such as timothy, foxtails, and brome grasses. Vegetation density does not appear to be important. Other important components of winter roosts are shelter from the weather, close proximity to a suitable hunting area, and lack of human disturbance. Once snow depths increase to 5 to 10 cm, or if the ground becomes very wet, Short-eared Owls start to roost in coniferous trees.

Potential Development Effects

Development occurring in field/meadow habitat is likely to result in abandonment of roosting areas. This has the potential to affect a large number of birds. Because roosts tend to be used year after year, loss of one site has the potential to affect wintering populations over a large geographic area.

Development on adjacent land has the potential to have impacts on winter roosts. Modification to vegetation structure or drainage patterns in the field supporting the roost may make it unattractive to harriers or owls. The same is true of fields that are used for hunting, which often is not the same area that the roost is situated in. Changes to vegetation and particularly alterations which reduce vole populations may also result in abandonment of the roost.

These two species are highly susceptible to disturbance while they are concentrated in roosts. Flushing of birds from roosts uses up valuable energy and can affect winter survival potential if disturbance is frequent. Regular disturbance is likely to result in abandonment of the site.

An increase in the number of cats may result in competition for prey. Studies have indicated that cats often reduce vole populations to levels where they are insufficient to support wintering raptors.

Mitigation

An Impact Assessment where raptor roosts are known or suspected would have to cover the winter period. Often Impact Assessments focus on the breeding season and ignore the winter.

It is unlikely that it will be possible to mitigate the effects of development in field/meadow habitat functioning as a winter roosting area for raptors, unless it is a single house. Avoidance of winter roosting areas by development is the optimum mitigation.

It may also be very difficult to mitigate the affects of human disturbance as a result of large-scale developments. Chain-link fencing may help to reduce the frequency of disturbance, but this may not always be effective. Disturbance due to pets and competition for food by cats will also be difficult to keep to acceptable levels.

If human activity is not expected to increase in the area, then steps should be taken to ensure that existing plant communities are not affected. Drainage should not be changed and the vegetative structure should be kept the same.

If development is proposed adjacent to fields used for hunting by wintering harriers or Short-eared Owls, the area should be kept as attractive to small mammal populations as possible. This requires a diverse plant community and a structurally complex ground layer. In some instances the loss of field area can be compensated by improvements to the remaining plant community to increase its diversity. Hiding cover and linkages between different areas of the field and nearby fields can be constructed to enhance the habitat for small mammal populations.

Attempts should be made to prevent fields from being greatly reduced in size. This may involve the clustering of development at margins of open areas. If field size is reduced, raptors may abandon roosts or feeding sites. Fields smaller than about 15 ha may not have sufficient small mammals to support wintering raptors and fields smaller than 20 ha are rarely used as winter roosts by harriers or Short-eared Owls.


Index #11 - Field/Meadows/Waterfowl/Rare or Specialized Habitat/Nesting Areas
Index # 11

Habitat Type:	Field/Meadows

Species Group: 	Waterfowl: Canada Goose, Green-winged Teal, American Black Duck, Mallard, Northern Pintail, Blue-winged Teal, Northern Shoveler, Gadwall, American Wigeon

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat: 	Nesting Areas

Habitat Function and Composition

This group of waterfowl commonly nests in upland habitat, usually grasslands, located near marshes and other wetlands, ponds, and lakes. Most nests are located within 100 m of water but it is not unusual to find nests 500 m or more from the water's edge. Once the eggs hatch, hens lead their broods overland to the water.

The wetland itself is used heavily by these birds throughout the year, but for successful reproduction, marshes must have an adequate supply of adjacent upland area offering habitat suitable for nesting. Without an adequate supply of nesting habitat surrounding wetlands, ducks will be forced to nest in poor quality sites. This results in low reproductive success and ultimately a decline in duck numbers.

Most waterfowl in this group select upland areas composed of grasses, sedges, rushes, and low shrubs. Some species will use adjacent hay fields as nesting sites. The black duck is known to nest in upland forest habitat. The exact species composition of the plant community seems to be a secondary consideration to the structure provided. Upland habitat adjacent to a wetland should be wide enough so that predators like raccoons, red foxes, coyotes, and striped skunks have difficulty locating nests. These bands of cover around a wetland generally experience very high rates of nest predation.

The following table summarizes the general habitat characteristics of waterfowl species that usually nest in field/meadow habitat.

Species	Habitat Characteristics
Canada Goose	Usually nests within 45 m of water; prefers vegetation less than 1 m tall unless it can find a hummock or mound to nest on
Green-winged Teal	Usually nests 35 to 55 m away from water; prefers dense vegetation and the nest is often at the base of a tree or shrub, in a clump of vegetation, or on a hummock
American Black Duck	Most nests are near water or even over it, but nests have been found as far as 800 m from water; prefers tall grasses and sedges for nesting; will nest in upland forest containing beaver ponds or other water bodies
Mallard	Not very selective in its nesting habitat; nests may be over water, very near it, or 1.6 km away; nests in urban areas, farmland and natural habitat; no strong preferences for vegetation height or type near the nest
Northern Pintail	Usually nests within 90 m of water; prefers sparsely vegetated areas and often nests on bare soil, including agricultural land
Blue-winged Teal	Most nests are within 45 m of water, but they have been found 230 m away in Ontario; prefers short, dense grass cover, especially Kentucky bluegrass
Northern Shoveler	Most nests are within 45 m of water, almost all are within 90 m; prefers perennial grasses and forbs about 50 cm in height
Gadwall	Most nests are within 45 m of water, but they may be as far away as 1.6 km; prefers extremely dense, tall vegetation 1.5 to 1.8 m in height, often nettles thistles, or shrubby areas
American Wigeon	Most nests are within 50 m of water, but they have been found as far away as 180 m; prefers dense cover of grasses or rushes

For most species, except the pintail, presence of residual vegetation from previous years is important.

Potential Development Effects

In the context of waterfowl nesting habitat, most development effects can be considered as those affecting the land adjacent to wetlands (i.e. impacts within 120 m of wetlands). Over 90% of waterfowl nests are likely to occur within 120 m of water.

Development on grasslands adjacent to wetland habitat can significantly reduce the function of upland habitat as waterfowl nesting areas. The loss of extensive areas of grassland habitat represents the greatest effect. As the supply of nesting habitat surrounding wetlands is reduced so too is the productive capability of the wetland for waterfowl (i.e. fewer areas to nest and reduced nesting success).

Building and lot-clearing activities which result in a simplified structural complexity of grassland habitat (i.e. mowing, lawn planting, etc) will disrupt or eliminate the function of nesting habitat.

Site alterations which isolate nesting habitat from the wetlands pose a hazard to ducklings. Once eggs have hatched, the hen leads the ducklings to the marsh. If they have to walk through open areas, the brood is exposed to mortality from avian predators, etc. Roads built between the marsh and nesting habitat present difficulties for broods moving to wetlands. If traffic is heavy, road mortality of ducklings is likely. Hens may try to direct their broods around barriers like roads and buildings etc. This leaves ducklings exposed to predators for longer periods of time, reducing their chances of survival.

Developments will likely increase human activity and the number of pets within nesting areas. Disturbance effects and nest predation by cats and dogs will lead to reduced brood success. If disturbance is frequent, nesting may be prevented entirely. Predators such as raccoons, gulls, and skunks appear to be attracted to areas of human activity. These predators can kill nesting ducks and destroy eggs. If the adjacent land is reduced to a thin band, virtually all production may be lost to predators.

Mitigation

Mitigating effects of development on the function of waterfowl nesting habitat involves careful planning of the location of roads, buildings, etc., on land adjacent to wetlands (i.e. within about 120 m). Areas of extensive grassland next to water should be avoided for development. If these areas must be developed, there may be opportunity to reconstruct (or establish) nesting habitat in other areas away from development. Reconstruction would involve establishing large areas (i.e. 4 to 10 ha) of upland grassland habitat which is not isolated from the wetland. The growth of native wet meadow (sedges, rushes, etc.) and grassland plants should be encouraged. Steps should be taken to prevent the invasion of nesting habitat by trees. Tallgrass prairie species such as big bluestem, indian grass, and switch grass provide excellent nesting habitat.

Human disturbance effects on nesting habitat can be minimized by ensuring that roads, paths, or other recreation facilities (golf courses, soccer fields, etc.) are not located near nesting habitat. These structures and facilities should not be built where they isolate the nesting habitat from the wetland. Nor should they reduce grassland cover to a thin band that is ineffective nesting cover. Large blocks of cover are preferred. It is possible to build predator enclosures around active nests. This is a labour-intensive activity which must be undertaken annually.

Grasslands should not be mowed. Large back yards in lots should not be considered grassland habitat when preparing the Impact Assessment.


Index #12 - Field/Meadow Habitat/Colonially-Nesting Birds/Habitat of Species of Conservation Concern/Breeding Habitat
Index # 12

Habitat Type: 	Field/Meadow Habitat; Prairie/Alvar/Savannah

Species Group: 	Colonially-Nesting Birds: Northern Harrier, Upland Sandpiper, Short-eared Owl [VULNERABLE], Henslow’s Sparrow [ENDANGERED], Grasshopper Sparrow

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat:	Breeding Habitat

Habitat Function and Composition

A number of Ontario’s birds require areas of relatively large, open grasslands or shrublands. Other species nesting in these habitats may not require extensive areas, but have very specific habitat requirements which limit their distribution. For these species, grasslands and shrubby areas provide essential food, cover and nesting habitat. A subset of these species also nest colonially in grassland, prairie, alvar, and savannah habitats. Colonially-nesting birds tend to nest close together, leaving much of the apparently suitable habitat unused. Colonial birds are highly susceptible to the effects of development, as impacts on a colony may affect regional populations.

The primary requirements of these open-country birds is highly variable, but they represent an open-habitat guild because they either require extensive areas of open habitat or have very specific habitat requirements. In addition, they tend to nest together in loose colonies. The following table outlines the general habitat requirements of grassland and shrubland birds of conservation concern.

Species	Habitat Characteristics
Northern Harrier	Prefers large, open fields with minimal shrub or tree coverage; individual birds seem to prefer open areas that are 30 ha in area or larger, but occasionally nest in smaller habitat patches; colonies tend to be small (2 to 5 pairs) and are associated with habitat patches 400 ha or larger; also nests in marshes, bogs, and fens; in fields, grass cover taller than 50 cm is preferred and the nest is often situated on a small knoll
Upland Sandpiper	Nests in old fields, hayfields, pastures, and at airports; may have originally been associated with short-grass prairie, also occurs on alvars; appears to require about 25 to 50 ha of open habitat for a single pair; colonies are usually associated with 200 ha or more of suitable habitat; prefers uniform grass cover 15 to 30 cm in height, avoids areas where grass height exceeds 60 cm; presence of residual vegetation from previous years is important; needs perches for displaying such as fenceposts
Short-eared Owl	Prefers grasslands of various heights, densities and species compositions; also nests in bogs, fens, and marshes and on extensive sand dunes; appears to require about 75 to 100 ha of contiguous open habitat for a single pair; colonies are usually associated with 500 ha or more of suitable habitat; nests tend to be in grass 30 to 50 cm tall, occasionally in vegetation as tall as 1 m; nests are often on knolls elevated 1 or 2 m above the remainder of the field
Grasshopper Sparrow	Often associated with areas of poor soils such as abandoned gravel pits or areas where bedrock is close to the surface; appears to prefer areas where vegetation is sparse, yet where there is a thick thatch cover from previous year’s vegetation; prefers grassy areas, but will tolerate 10 to 20% shrub cover; prefers scattered shrubs or tall, sturdy, herbaceous vegetation stalks that can be used as singing perches; may nest singly or in small colonies of one or two dozen pairs; occurs in habitats as small as 10 ha when a single pair is nesting, but colonies are often associated with habitat patches 100 ha or larger
Henslow’s Sparrow	Originally associated with tall-grass prairie; nests in heavily-vegetated fields dominated by grass; prefers grass 1 m tall or more, but will use areas where grass is as short as 25 cm; tends to avoid fields where shrub coverage is much greater than 1%; tall, sturdy, herbaceous vegetation stalks are necessary for perching (common mullein, evening-primrose); low-lying (moist) fallow fields with an accumulation of dead plant material provide the highest quality habitat; long-term populations are associated with fields 40 ha in area or larger; colonies probably require 100 ha or more of suitable habitat
Potential Development Effects

Grassland and shrubland species are considerably at risk because the habitat that they depend on is generally considered wasteland with limited ecological value. These habitats are often considered prime development areas, and they are often planted to trees. Most of these species are experiencing declines. Colonies are particularly at risk because of the larger area that is required to support a colony as opposed to a single pair. Loss of a small portion of the habitat may result in loss of most, if not all, of the colony. The persistence of a residual one or two pairs should not be considered acceptable if a colony is lost or significantly diminished in size.

Development which affects habitat supporting any of these bird species will affect the use of this significant wildlife habitat. The Henslow's Sparrow is endangered in Ontario and development is not permitted within the significant portions of the habitat of this species (Natural Heritage Policy 2.3). The Ministry of Natural Resources must be consulted for any development proposal that may affect Henslow’s Sparrows. The Short-eared Owl is considered vulnerable in the province, and the guidelines for the PPS suggest that, at a minimum, the best examples of habitat for vulnerable species should be maintained.

Excavation or construction which reduces the amount of suitable habitat will affect the number of birds which can use the field for breeding. Most birds are territorial during the nesting season and must retain a large enough area to forage and provide for their developing offspring.  Even colonially-nesting species defend a small area around the nest. Reductions in the amount of field area will translate in the loss of nesting territories or a reduction in the amount of food available to birds using the restricted habitat area. The net result is a reduction in brood success. Loss of suitable habitat is particularly critical to these colonial species that require a large patch of suitable habitat. Decreasing the amount of grassland habitat below a species' threshold size may result in its abandoning the area or most of the colony members disappearing.

Site alterations which change the composition or structure (i.e. establishing lawns, etc.) or which result in the conversion of open areas to forest (i.e. tree planting or prevention of fire or grazing which once kept the area open) will have negative impacts on grassland birds. The above table demonstrates that many of these species have very specific microhabitat requirements; any changes in these will be detrimental.

Residential developments which result in there being many free-ranging pets (cats and dogs) and urban wildlife species (skunks, raccoons) will affect nest success by introducing significant predation to the area. Cats are also significant competitors for prey for species such as Northern Harrier and Short-eared Owl.

The two raptor species in this guild are susceptible to human disturbance. Human incursion into the nesting habitat may result in nest abandonment, or predators may follow human trails to find nests.

All of the species in this group nest on the ground and have very specific soil moisture requirements. Development which results in fields becoming drier or wetter may result in abandonment of the area by the species of concern.

Mitigation

Development should not reduce the amount of suitable habitat below the threshold size required by colonies of any area-sensitive species that occur in the area. Generally, if the amount of habitat that remains is large enough to support the most sensitive species, all other species should be protected. Therefore, a good inventory of the species that are using a particular site is very important.

The area left should be in one large patch rather than broken up with large rural lots where the lots have been included as part of the total grassland habitat. Patch shape is also important, much the same as for interior forest. Clustering development may reduce the amount of habitat that is affected.

Impact Assessments should address drainage, habitat structure, and human and pet usage. Stormwater management studies and, in some cases, hydrogeological studies, will be required to determine if changes in grassland moisture regimes will occur. If changes may occur, then impacts on vegetation composition and structure should be determined along with ramifications on significant grassland and shrubland species. The Henslow’s Sparrow requires tall, thick grass cover and is particularly vulnerable to a site becoming drier.

Even if drainage patterns and most of the grassland/shrubland is maintained, management (or lack of intervention) may be required. Landowners may consider an adjacent old field to be a weedy eyesore. The temptation to plant trees or mowing must be averted. Interpretational signs or other educational techniques should be employed so that residents understand that they are living adjacent to significant species and their habitat. However, the reality is that interpretation often does not work.


Index #13 - Open Water Shoreline/Amphibians/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 13

Habitat Type: 	Open Water Shoreline

Species Group:  	Amphibians: Fowler’s toad [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

The Fowler’s toad is restricted in Ontario to the shores of Lake Erie. This toad prefers to live on sandy beaches associated with lakes and rivers.

During the day, Fowler’s toads escape the sun by burrowing into the sand. They emerge at night to forage. Eggs are laid in quiet shallow water. Toads hibernate by burrowing more than 1 m into beach sand.

For an area to function as Fowler’s toad habitat it must provide sand beach adjacent to open water of lakes, rivers, or large marshes. Areas of natural beach vegetation are important features promoting an abundant supply of insects.

Potential Development Effects

Development which involves site alterations to shoreline beaches have the greatest potential to affect Fowler’s toad populations. Construction of breakwalls and other structures which prevent access to open water from the beach will disrupt the function of shorelines as Fowler’s toad habitat.

Residential or recreational developments which cause increased human activity on beaches during summer will affect Fowler’s toad use of the area. Heavily-used sections of beaches may be abandoned.

Development on adjacent land is not expected to affect Fowler’s toad habitat unless it results in an increase in human activity on the nearby beach during summer.

Mitigation

Successful mitigation of the effects of development on Fowler’s toad habitat involves ensuring that not all beach areas are developed or otherwise used by humans during summer. Sections of beaches should be left in a natural state and plants and natural debris (driftwood, etc.) should be allowed to accumulate.

Development should be set back from known Fowler’s toad habitat.


Index #14 - Open Water Shoreline/Wetland/Amphibian/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 14

Habitat Type: 	Open Water Shoreline; Wetland

Species Group:  	Amphibian: bullfrog

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Bullfrogs are highly aquatic and live in permanent water near the shorelines of lakes, large marshes, and slow-moving rivers. Extensive areas of emergent shoreline vegetation are required for breeding. Eggs are laid near shore in floating mats of jelly. It takes 2 to 4 years for tadpoles to transform into adult form frogs and another 3 to 5 years to mature to breeding adults (depending on geographic location). Bullfrogs hibernate in bottom sediments. They are intolerant of freezing and are therefore prone to overwinter mortality in areas where water-level fluctuations occur.

For a section of shoreline to function as bullfrog habitat it must provide deep, permanent water with abundant emergent plants. Emergent plants support high densities of invertebrates which are consumed by larval frogs. The vegetation also provides hiding cover for tadpoles which are eaten by many predators. Water-level stability is also required to prevent desiccation of spawn during early summer and freezing during hibernation.

Potential Development Effects

Development which involves shorelines of lakes, marshes, and slow-moving rivers may affect bullfrog populations. The degree of impact will depend on how water levels and aquatic plants are affected.

Dredging and filling of shoreline areas which results in a permanent loss of emergent vegetation from the shoreline will result in the loss of the area’s function as bullfrog habitat. As vegetation is removed mortality among tadpoles and adults is likely to increase. Given the long time it takes for bullfrogs to mature, increased mortality rates in a population can have significant impacts on reproduction and hence recruitment (a measure of the number of individuals added to the population).

Development which results in seasonal water-level fluctuations may seriously affect bullfrog populations owing to effects on floating egg masses during early summer and by leading to high overwinter mortality of hibernating frogs.

Increased human activity along the shoreline may lead to illegal hunting of bullfrogs and loss of shoreline vegetation.

Development on adjacent land may affect bullfrog populations if it results in water-level fluctuations or changes in water quality (water clarity, pollution, etc.). Bullfrogs and other amphibians are susceptible to environmental contaminants and could be affected by stormwater in a number of manners. In areas of high traffic volumes, heavy metals may accumulate due to wear of vehicle brakes and engines. These have the potential to bioaccumulate and reduce bullfrog populations.  Traffic from adjacent development may result in road mortality during migration. Sediment and nutrient inputs can reduce water clarity and the amount of aquatic vegetation, thereby impairing bullfrog habitat. High nutrient concentrations can reduce dissolved oxygen concentrations in water, which could result in overwinter mortality of tadpoles or adults. Increased predation may result from urban wildlife species such as raccoons.

Mitigation

Mitigation of the effects of development on bullfrog habitat involves restriction of shoreline site alterations which remove emergent plants and careful consideration of water control activities which result in drawdowns during autumn/winter and early summer.

To protect areas of high bullfrog use, development should be set back from the shoreline. The key is to preserve shoreline, near-shore vegetation, and water structure (logs, stumps, rocks, etc.).

Stormwater should not be discharged directly into water bodies supporting bullfrog populations. Sediment forebays and regular maintenance and clean out should be required for stormwater facilities that will ultimately discharge to bullfrog habitat.

An early summer survey should be conducted in potential bullfrog habitat to determine if sites are used for breeding. Chorusing males are evident at this time.


Index #15 - Open Water Shoreline/Prairie/Alvar/Savannah/Insects/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 15

Habitat Type: 	Open Water Shoreline; Prairie/Alvar/Savannah

Species Group:  	Insects: Karner blue butterfly [ENDANGERED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

The Karner blue butterfly exists in small isolated populations throughout its eastern North American range. Populations are established in areas like pine barrens, beach dunes and other habitats providing populations of their host plants, lupine (Lupinus perennis).

Adult butterflies emerge twice each growing season, once in May to June and again in July to August. Eggs are laid on various parts of their host plant. Caterpillars feed on young leaves of lupines and are tended by ants which feed on sugary secretions exuded from the caterpillar’s abdominal glands.

The fact that Karner blue populations exist in small localized populations is significant. These small populations are prone to local extinctions. Areas of suitable habitat are re-colonized from surrounding sub-populations. In this light, finding areas with suitable habitat which contains no Karner blues  is not surprising. In time these patches of habitat may be re-colonized but only if patches of suitable habitat are protected (i.e. whether inhabited or not).

 For an area to function as Karner blue habitat it must provide relatively large populations of their host plant - lupine. These plants grow in dry sandy soils. Beach dunes, pine barrens and pine-oak savannahs are preferred habitats.

No information is available on minimum patch size to support a viable population of Karner blues. The area required will depend on whether there is other suitable habitat nearby, or if the site is isolated. Isolated sites must be larger because there is unlikely to be recruitment from other areas. To maintain genetically-viable populations of plants or animals, it has been determined that approximately 500 breeding adults are required to prevent genetic drift and 50 are necessary to prevent inbreeding. For developments that may affect Karner blue habitat, the Impact Assessment should determine the current population size and amount of habitat required to support a viable population of both lupines and Karner blues.

Potential Development Effects

Development in areas of pine barrens, beach dunes or shoreline areas with populations of lupine plants will affect Karner blue butterfly habitat.

Excavation and construction which eliminates lupine populations will destroy the function of the area for Karner blues.

Development on adjacent land is not expected to impact Karner blue butterfly habitat provided that people do not trample, pick, or otherwise destroy their host plants.

Another lupine (Lupinus polyphyllus) is native to western North America, but is widely planted in gardens in Ontario. It readily becomes established in roadsides and other disturbed areas. It has not been documented as hybridizing with Lupinus perennis but it could possibly spread from gardens and crowd out the native species. It is unknown if Karner blues will use the garden lupine, and if reproduction will be successful if they do.

White-tailed deer are known to feed on lupines, and this was a problem for the lupine population at Pinery Provincial Park. Large subdivisions or expansions of urban areas may eliminate deer hunting seasons. This may result in locally high deer populations which may decrease lupine populations and have an effect on Karner blues.

Mitigation

It will not be possible to mitigate the effects of development on Karner blue habitat if populations of lupine will be denuded. Attempts to establish lupine populations in areas away from the development may be successful provided that areas of favourable growing conditions are available.

Development should be designed to avoid areas of Karner blue habitat and provide a suitable setback to protect prime areas. Ideally, all areas supporting lupines should be protected, and the Impact Assessment should determine area required to support viable populations of both lupines and Karner blues.

Human usage of areas supporting lupines should be restricted. Motorized vehicles, such as dirt bikes, should be prohibited in areas where lupines are growing.

The Karner blue is protected under the Ontario Endangered Species Act. Development is not permitted in the significant portions of its habitat (Policy 2.3 of the Provincial Policy Statement), which is predominantly areas supporting lupine populations. Any development that has a potential to affect Karner blue habitat should be referred to the Ministry of Natural Resources.


Index #16 - Open Water Shoreline/Woodland/Forest/Reptile/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 16

Habitat Type:	Open Water Shoreline; Woodland/Forest

Species Group: 	Reptile: five-lined skink [VULNERABLE]

Significant Wildlife Habitat Category:	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Five-lined skinks are found in two rather different habitat settings in Ontario. Skinks occur among the sandy beaches and dunes of Lake Erie and Lake Ontario shorelines as well as in barren rock/woodland settings of the Canadian Shield.

In shoreline habitat skinks prefer undisturbed areas of beaches and dunes which have some vegetation cover. Downed woody debris and other structures which provide hiding cover are very significant habitat elements. This structure allows skinks to avoid predation from the many gulls which frequent these shoreline areas. Skinks spend considerable time basking in sunlight.

For a shoreline area to function as skink habitat it must provide undisturbed vegetated areas.  A key feature of skink habitat is an abundance of ground-level structure. Downed woody debris, rocks, and other structures that skinks can hide in or under contribute much to reproduction and survival.

On the Shield, skinks prefer moist woods with forest openings. Many of these openings are rocky outcrops which are used for basking. Downed woody debris and light sandy soil are very significant habitat elements. Skinks are found frequently under logs, deep leaf litter, rocks, sawdust piles, etc. Eggs are laid in rotting logs or light soil, often under logs or rocks. Females sometimes guard eggs, and there may be multiple clutches laid by several females. Skinks hibernate in rotting logs or underground below the frost line. They also spend considerable time basking in the sun on rocks, or on rock outcroppings in open areas.

For a woodland area to function as skink habitat, it must have a moist understory. Skinks are generally found close to permanent water. These conditions are usually provided by mature deciduous or mixedwood stands. Forest openings are important elements. Openings may be provided by gaps in the forest canopy due to tree fall or cutting, or by areas of rock outcroppings. Downed woody debris, much of which is in an advanced state of decay, as well as rocks and other structures that skinks can hide in or under contribute much to reproduction and survival.

Skinks may be locally abundant throughout their range, but they tend to be discontinuous in distribution.

Potential Development Effects

Development which affects shoreline areas or moist woodlands has the potential to impact significant portions of preferred skink habitat owing to their high dependence on these habitats. Since the distribution of skink populations tends to be patchy, development in areas where skinks are abundant can potentially affect an entire local population.

Excavation, road and building construction may have major impacts on skink populations. Roads may act as barriers to skink movement and may increase mortality rates. Tree-cutting and lot-clearing activities further reduce the quantity of remaining shoreline or woodland habitat for skinks. The loss of downed woody debris and other structural elements of beach, dune, or forest floor habitat greatly reduces the utility of the area for skinks.

Development on adjacent land is not expected to directly affect skink populations in their preferred habitat. Roads adjacent to preferred habitat may still result in barriers and roadkill. Development on adjacent lands that affects moisture regimes in woodland habitat may be detrimental to skink populations.

Increased human usage can have negative impacts on skink habitat. Degradation of vegetation and loss of ground structure may occur, and structural loss may reduce habitat suitability and food supply for skinks. Urban species such as skunks, raccoons, and pets may result in increased predation. Children may also collect skinks as pets.

Mitigation

Mitigating the effect of development on five-lined skink habitat in shoreline habitat involves protection of adequate areas of beach from development and human activity. Areas of natural vegetation and accumulated driftwood, etc. should be protected or enhanced.

Any development that has the potential to affect skink populations should attempt to determine if the population is isolated or part of a larger population. For isolated populations, enough area of suitable habitat must be maintained to support a viable population. About 500 breeding adults are necessary to prevent genetic drift and 50 are necessary to prevent inbreeding. When the area that may be affected is part of a larger population, the development must not result in the isolation of the population, allowing access to and from the area by skinks.

In woodland habitat, the amount of tree cutting in preferred habitat should be restricted. Skink populations may benefit by increasing the amount of downed woody debris and other forms of ground-level structure.

On lands adjacent to forested skink habitat, appropriate stormwater management or infiltration may be required to ensure that the forest floor does not become drier and that woodland pools do not dry up.


Index #17 - Open Water Shoreline/Prairie/Alvar/Savannah/Reptile/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 17

Habitat Type: 	Open Water Shoreline; Prairie/Alvar/Savannah

Species Group:  	Reptile: eastern hognose snake [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

The eastern hognose snake frequents areas of sandy soil such as beaches, dunes, old fields, and pine barrens.

These snakes prey primarily on toads and other amphibians. Eggs are laid in sand or rotting wood. Hognose snakes hibernate in woodlands under downed woody debris.

For an area to function as hognose snake habitat it must have sandy soil, an abundance of toads and other prey, and forested land with plenty of downed woody debris and other ground level structure. Pine forests with a low density of trees seem to provide the best habitat conditions during autumn and for winter hibernation.  Large forest areas (i.e. > 5 ha) seem to be preferred.

Potential Development Effects

Development which affects open, sparsely-vegetated areas with sandy soil or pine forests growing on light soil have the greatest potential to affect hognose snake habitat.

Tree cutting and lot clearing which reduces the availability of forest cover or which results in the establishment of forests with very simplified understories (i.e. little or no structure) will effectively reduce the amount of suitable hognose snake habitat in the area. If the area of adjacent forest is decreased below 5 ha, there may no longer be suitable habitat for hibernating. All parts of their habitat for the year must be maintained.

Road construction poses considerable risk to hognose snakes owing to the likely increase in mortality.

The hognose snake is often found in disturbed areas like roads, gardens, etc. This association has contributed to its decline in Ontario. Many snakes are killed by vehicles as they cross or bask on roads. Significant numbers of hognose snakes have been killed by people under the mistaken belief that they are harmful. This reputation is because of the hognose’s threat display. When provoked, these snakes flatten their head and neck, hiss and pump up their body making themselves look menacing. They will also lunge and strike.

Development in areas functioning as hognose snake habitat or in adjacent areas will increase mortality owing to indiscriminate killing of snakes thought to be dangerous. Development on adjacent lands may act as a barrier, isolating summer and winter habitat.

Any development activity that decreases amphibian populations will be detrimental to hognose snakes. Filling in ponds, altering beach habitat that is critical to toads, changing the hydrological cycle so that amphibian breeding ponds dry up before tadpoles can transform, or degrading water quality in breeding ponds will all have adverse impacts. Factors which reduce the quality of amphibian summer habitat will also have an effect on hognose snakes.

Mitigation

The effects of development can be made less severe for hognose snakes if relatively large areas of pine forest (i.e. > 5 ha) are left uncut or otherwise affected. Suitable woodlots should not be reduced below about 5 ha and care should be taken that key habitat features are maintained. For example, it would do little good to protect summer feeding habitat but then eliminate winter hibernation sites.

These snakes will benefit by a general restriction on lot-clearing activities. As much downed woody debris or other ground-level structure should be left intact. In areas where there is very little ground-level structure left, its supply can be increased relatively easily.

Roads should not be constructed between summer habitat and wintering sites. If this is essential, underpasses should be provided in key areas. Lower than normal speed limits and interpretive signage should be posted in an attempt to reduce mortality.

If possible, development should not occur between feeding and wintering areas. If development does proceed, corridors should be maintained through the development to link critical habitats.

Hognose snake populations would benefit from public education programs designed to dispel the myth that these snakes are dangerous. Also, people should be encouraged not to use herbicides and pesticides on their lawns and gardens, and these are excellent areas for toads.

Amphibian breeding ponds should not be filled in and their hydrology should be maintained. Aquatic vegetation and woody debris in amphibian breeding ponds should be kept intact. Stormwater should not be directed to amphibian breeding ponds unless it first goes to a settling basin and it can be demonstrated that water quality and water levels will not change so that amphibians are negatively affected.

Important summer habitat for amphibians should be identified and protected. Corridors for amphibian movement between breeding areas and summer habitat should be maintained so that prey for hognose snakes does not decline.

There may be opportunities for enhancing habitat for hognose snakes and their prey. This might be accomplished by adding more ground structure, creating breeding ponds for toads, and creating movement corridors for amphibians and snakes.


Index #18 - Open Water Shoreline/Reptile/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 18

Habitat Type: 	Open Water Shoreline

Species Group:  	Reptile: eastern spiny softshell turtle [THREATENED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

The eastern spiny softshell turtle frequents permanent water in large rivers, backwater areas of lakes, and wetlands having large areas of moderately deep open water associated with them. These turtles prey primarily on fish. Healthy prey populations and clean water are key elements to the survival of spiny softshell turtles. This species hibernates in bottom sediments.

For a river, lake or marsh to function as spiny softshell habitat it must provide an area of open water containing a diversity and abundance of emergent and submergent aquatic plants and large and productive fish populations. Areas of loose mud bottom sediments are required for hibernation. An abundance of structures in the water (i.e. logs, rocks, etc.) not only provide areas for fish production but they provide hiding places for young turtles where they can avoid predators. Adult turtles also use these structures as resting sites and places to hide as they wait for fish to swim within reach. This turtle spends much of its time buried under the sand or mud in water shallow enough that it can thrust its snout to the surface for air. Nests are dug in the loose soil of sandy beaches, gravel bars, or old road beds close to water.

The spiny softshell is considered threatened in Ontario. No development is permitted in the significant portions of its habitat according to Policy 2.3 of the Provincial Policy Statement. Significant spiny softshell habitat includes nesting areas and aquatic feeding habitat and corridors between critical areas.

Potential Development Effects

Developments which affect shorelines of large rivers and backwater areas of lakes and open-water areas of large marshes have the greatest potential to affect spiny softshell habitat.

Dredging and filling of nearshore areas of rivers and lakes will effectively reduce the amount of suitable spiny softshell habitat in the area. Any activity which negatively impacts nearshore fish populations will also affect these turtles. Activities which affect sand or gravel deposits near water may affect nest sites. Loss of or alteration of nesting habitat may reduce its size and make eggs more vulnerable to predation. Water-level fluctuations and winter water drawdowns can have adverse impacts on wintering turtles.

Development on adjacent lands may have negative impacts on spiny softshells. Increases in nutrient concentrations in critical water bodies may result from stormwater and fertilizers applied to lawns. This may promote algal growth which increases water turbidity. This may reduce the foraging efficiency of turtles, as they capture prey by sight. Increased turbidity also inhibits growth of aquatic plants, particularly submergents, with a subsequent loss of cover and fish habitat. Turbidity due to sedimentation from roads may create similar problems.

Roads very close to nesting areas may result in mortality. There is also a potential that roads or development may prevent turtles from reaching nest sites.

Residential developments often attract predatory mammals such as skunks and raccoons. An increase in the population of these species could result in decreased reproductive success because they prey on eggs and newly-hatched young.

Humans may disturb turtles while they are nesting or attempt to catch them as pets.

Mitigation

Mitigating the effects of development on spiny softshell turtle populations involves the maintenance of fish habitat and turtle nesting areas. Provisions made under the Fisheries Act for protecting fish habitat should benefit and protect aquatic habitat for these turtles. The Fisheries Act may not necessarily protect the nearshore (nesting) habitat, although often it will.

Development should not encroach too closely to shorelines so that egg laying and basking areas are not affected. It may be necessary to fence off critical nesting areas to prevent human disturbance. Ideally, fencing would also be predator-proof for species such as raccoons and skunks. Human activities should be prohibited in these areas, with no boat launches or swimming beaches.

Roads should not be built close to nesting areas or intercept movement areas between aquatic habitat and nest sites.

Stormwater management facilities that discharge into spiny softshell habitat should be designed to treat for water quality and quantity. There should be no discharge of untreated stormwater into spiny softshell habitat and treatment should not result in an increase in sediment or nutrient loading.

The shoreline should be kept natural adjacent to and in spiny softshell habitat. At a minimum, 30 m of natural shoreline should be maintained. In some cases, where the beach is wide or nesting areas are more distant from the water, it will be necessary to maintain a wider natural band along the shoreline.


Index #19 - Open Water Shoreline/Rare or Specialized Habitat/Shoreline Foraging and Den Sites/mink and river otter
Index # 19

Habitat Type: 	Open Water Shoreline

Species Group:  	mink and river otter

Significant Wildlife Habitat Category: 	Rare or Specialized Habitat

Functional Habitat: 	Shoreline Foraging and Den Sites

Habitat Function and Composition

Mink and otter rely primarily on aquatic ecosystems for food. Mink travel the shoreline while searching for their favourite foods: fish, small mammals (especially muskrats), frogs, crayfish, etc. Otter are less restricted to the shoreline for travel but spend much of their time foraging in the nearshore area for fish, crayfish, and frogs.

Both species rely on undisturbed shoreline habitat for denning. Dens are used for resting, escaping predators, protection during inclement weather, and for bearing and raising young. Mink generally den underground but will often use abandoned muskrat lodges. Otter frequently use old beaver lodges but may also den in log jams or jumbles of loose rock.

Since mink are more strongly tied to the shoreline for foraging than otters, they show greater affinity for specific shoreline vegetation conditions. Mink prefer shorelines dominated by coniferous or mixed forest cover. The species of coniferous trees in the area appears to be of secondary importance to the vertical structure and cool microclimate they provide. Studies in Ontario have shown that deciduous shorelines receive little use by mink. The structure of the forest understory is important to mink. Dens are located in areas having abundant shrubs providing horizontal cover. Stumps and deadfalls are usually more abundant in areas frequented by mink. This downed woody debris provides hiding cover and provides ideal habitat for small mammal prey. Coniferous and mixed forest shorelines adjacent to marsh habitat are particularly important, as marshes are likely to support muskrats, one of its preferred foods. A productive littoral zone with lots of cover and habitat for small fish and crayfish would be beneficial for both of these species.

Otter forage while swimming, so shoreline vegetation is not as significant in determining their distribution. However, they do need undisturbed shorelines for denning. Forests providing abundant shrubs and downed woody debris are needed for successful reproduction. Since otter prey mainly on fish, clams, and other aquatic organisms, they require nearshore habitats containing relatively large and productive fish populations.

Potential Development Effects

Development can affect mink and otter abundance significantly if it occurs in sections of shoreline dominated by coniferous or mixed forests or if site alterations affect fish habitat or marsh vegetation. The effect will be greatest if the shoreline is already developed and there is relatively little undisturbed area left. Mink may be severely affected by lot-clearing activity. As the forest understory is simplified, food supplies and the availability of suitable denning sites will be reduced. The carrying capacity for both species will be reduced if development decreases the abundance of submergent, emergent or floating aquatic vegetation or involves the removal of boulders, stones or submerged logs, owing to negative effects on muskrats, fish and other aquatic organisms (crayfish, frogs).

Development on lands adjacent to foraging or denning sites may also affect mink and otter particularly if it involves the immediate shoreline (i.e. within 10 m of waterline) or the littoral zone. The primary effect would involve disruption of mink and otter movement among suitable habitat and a reduction in prey populations. Buildings near the shoreline may affect the movement of mink as they forage along the shoreline. Mink and otter may also be prevented from moving among feeding and denning sites. Mink and otter have large territories and continually move through their ranges in search of food except perhaps in denning season. Loss of shoreline cover may disrupt movement and make parts of their habitat unusable.

Stormwater has the potential to affect habitat for muskrat and fish. Changes in water levels or the frequency and magnitude of water-level fluctuations may alter the distribution of aquatic plants. This, in turn, may result in a decline in usage of the near shore area by fish and muskrats. Excessive nutrient or sediment delivery to the water body will also affect fish habitat and the distribution of aquatic vegetation.

Frequent human usage along shorelines may totally disrupt mink movement. Construction of docks, clearing shoreline and aquatic vegetation to create beaches, and consistent human presence may discourage mink from using areas.

Mitigation

Development effects on mink and otter populations can be reduced if site alterations are directed away from shorelines supporting coniferous or mixed forests. Shoreline development should be set back from the water's edge. A setback of 30 m is suggested as a guideline. An Impact Assessment may be able to demonstrate that a narrower setback will maintain shoreline function for mink and otter habitat. In some instances, a wider setback may be required to fully maintain functions. Setbacks not only protect fish and marsh habitat, but allow mink and otter to move along the shoreline. Protection of the shoreline vegetation ensures there will be a variety of prey available. Multi-lot developments should be planned so that structures are clustered back from the shoreline to keep the shoreline natural. There should be one common access point to the shoreline for boating and swimming. These areas should be kept as small as possible, and mink will cross areas such as these.

Minimizing lot-clearing activities will be beneficial by maintaining mink foraging areas and mink and otter denning sites. Attempts should be made to ensure that no site alterations affect the immediate shoreline area. This applies to the significant wildlife habitat as well as the adjacent lands. Shoreline areas can be made more suitable for mink by increasing the structural complexity of the forest understory and increasing the coniferous component of the overstory. Tree planting and the addition of downed woody debris can be used to improve habitat for mink and otter.

Increasing the structural complexity of the littoral zone can improve the overall suitability of foraging areas for mink and otter if they increase muskrat, fish, or crayfish abundance. This has the potential to improve fish populations as well as help these and other wildlife species. Maintenance of shoreline aquatic vegetation will ensure habitat for amphibians like frogs, thereby maintaining another valuable food resource for these carnivores.

During site alteration, sediment controls should be installed and maintained to ensure that sediments do not reach aquatic or wetland habitat. For large-scale developments, stormwater management facilities should be designed to keep levels of nutrients and sediments in the water body or wetland at acceptable levels.

Septic systems should be well designed and maintained on a regular basis.


Index #20 - Open Water Shoreline/Wetlands/moose/Rare or Specialized Habitats/Aquatic Feeding Area
Index # 20

Habitat Type: 	Open Water Shoreline; Wetlands

Species Group:  	moose

Significant Wildlife Habitat Category: 	Rare or Specialized Habitats

Functional Habitat: 	Aquatic Feeding Area

Habitat Function and Composition

From June through July moose consume large quantities of aquatic plants. Their selection of aquatic plants is linked to a need for sodium since these plants have relatively high concentrations of this essential element. Moose require sodium at this time of year for antler development and lactation, as well as basic neurophysiological functions. During spring and summer moose consume terrestrial plants which are much higher in potassium than sodium. This dietary imbalance in the ratio of potassium to sodium ingested results in flushing of sodium from the body. As a result moose develop considerable “thirst” for salt which they satisfy with a diet of aquatic plants.

Moose may move considerable distances to reach preferred feeding sites (as far as 30 km). They feed several times a day for about an hour at a time. Submergent vegetation is used more frequently than emergent aquatic plants. Moose select species with the highest sodium concentration.

For an area to function as an aquatic feeding area it must have an abundance of preferred aquatic plants located in an undisturbed site with nearby forest habitat providing shade and hiding cover. Pondweeds, yellow water-lily, and water-milfoil are preferred species but moose will use a variety of plants. Moose use areas of lowland conifer located near aquatic feeding areas during the warmest part of the day to reduce the effects of heat stress. An ideal arrangement is to have areas of abundant submergent aquatic plants adjacent to stands of lowland conifer. Aquatic feeding areas include both the nearshore area providing plant material and the adjacent forest cover.

Potential Development Effects

Development has the greatest potential to disrupt the function of a site as an aquatic feeding area if it involves shoreline site alteration and increased human disturbance during summer.

An increase in human activity in the nearshore area associated with the aquatic feeding area will reduce its use by moose since moose are intolerant of human disturbance. Any changes to local water-level fluctuations associated with the development could alter the quantity and species composition of aquatic plant community. These changes may affect the quality of the feeding site and if impacts are severe, the area may be rendered useless as an aquatic feeding site. Increases in boat traffic associated with development will likely cause moose to abandon the area. This impact extends to development on adjacent lands since increased boat traffic, no matter where it originates from, will affect moose.

Development which occurs in the forest cover associated with the feeding site will have similar impacts on feeding site function as developments which impact the aquatic plant community. Human activity along the shoreline will displace moose to distant areas of conifer cover. If development, and in particular associated human activity, are visible from the shoreline aquatic feeding site, moose will probably abandon the site.

Since aquatic feeding areas occur in limited supply and serve an important physiological function, any impacts on feeding areas will affect the summer carrying capacity for moose.

Dredging and dock construction may have significant impacts on the near shore aquatic plant community hence food supplies. Since docks are sites of increased human activity, they present particular risk as far as moose abandoning a feeding site are concerned. Docks which will not be used or which will not attract boat activity during spring and early summer will have benign effects. Dock construction on adjacent lands may present a threat to feeding area function depending on where anticipated boat traffic is likely to occur.

Timber clearing and building construction in conifer cover located near the area where aquatic plants are abundant will reduce the quality of the aquatic feeding site.

Activities, such as site clearing and discharge of stormwater, which may affect sediment and nutrient concentrations in aquatic or wetland habitat may alter plant populations. This can reduce the quality of moose-feeding habitat. Submergent aquatic vegetation is particularly susceptible to increases in nutrient concentrations and turbidity.

Mitigation

Important moose aquatic feeding habitats should be identified as significant wildlife habitat. This habitat should also include any adjacent lowland coniferous forest because of its value as a cool area to rest. Development proposals should be designed so that they do not affect these habitats. A visual barrier should be maintained between any development and aquatic feeding habitat. Proponents should refer to the “Timber Management Guidelines for the Protection of Moose Aquatic Feeding Habitat”.

Mitigating the effects of development on aquatic feeding may not be possible owing to the sensitivity of moose to human disturbance. Large-scale developments, in particular, may not be compatible with aquatic feeding areas for moose.

Single-lot development may not affect the site if structures are not visible from the nearshore area of the feeding area. Steps must also be taken to ensure that human activity is restricted to areas away from the shoreline.

If development occurs on adjacent land then boating traffic should be managed and directed away from the feeding site if possible. Even a moderate increase in boat activity would reduce the quality of the feeding site. Access points should be planned so that boat traffic is not funnelled through aquatic feeding areas. Small lakes may require a ban on motorboat traffic to retain the function of aquatic feeding areas.

Often the lower ends and mouths of slow-moving creeks provide excellent aquatic feeding habitat. These areas should not be developed, and boat traffic should be restricted in these sites.


Index #21 - On Water Shoreline/moose/Rare or Specialized Habitat/Calving Sites
Index # 21

Habitat Type: 	On Water Shoreline

Species Group:  	moose

Significant Wildlife Habitat Category: 	Rare or Specialized Habitat

Functional Habitat: 	Calving Sites

Habitat Function and Composition

Cow moose isolate themselves from other moose shortly before giving birth in late May to the end of June. Islands and peninsulas appear to provide the most desirable calving sites although habitat selection is highly variable. Isolation in these habitats helps cows to avoid predators by making them more difficult to find and islands and peninsulas provide convenient access to water for escape from predators. Wolves do not frequent islands during ice-free months and black bears seem to prefer mainland areas. Isolation from other moose at this time helps ensure that newborn calves imprint successfully on their own mother. This strengthens the cow/calf bond increasing the chances of survival for the young and vulnerable moose. The first few hours after birth are the most critical for the new-born calf.

Some calving sites show repeated use by cows year after year while others are used intermittently. Cows and calves may stay in calving sites for 4 or 5 weeks after birth. After about 5 weeks the calves are able to follow their mothers easily and sites are abandoned.

The composition and structure of forest cover associated with calving sites varies considerably. Though forest composition does not present an accurate or precise prediction of use by moose,  biologists have ranked broad habitat types as to their quality as calving sites. Islands and peninsulas are accepted as providing the best habitat followed by shoreline (< 100 m from open water) and upland area 100 to 500 m from open water. Wetlands and upland habitats > 500 m from water, though sometimes used as calving sites, are considered low quality.

The actual calving site is usually elevated providing the cow a good vantage point to spot approaching danger. Calving sites are difficult to find unless thorough surveys are conducted.

Potential Development Effects

Development proposed for island, peninsula or shoreline areas, has the potential to disrupt the function of the area as a calving site. The primary factor affecting moose is human disturbance. Presence of pets, particularly dogs, during the calving season may cause moose to stop using the site for calving. Any permanent structures used by people during the calving season will cause moose to stop using the site for calving. If these sites are islands or peninsulas, then there will be a loss of prime calving sites and if development in these types of settings is widespread, then there may be significant impacts on the reproduction of moose within the region.

Development on adjacent lands can cause moose to abandon the site if human or pet activity in the area is increased, even marginally, during the calving season.

Site alterations which remove extensive forest cover may cause moose to abandon the area as a calving site. Structures may not affect moose use of the area provided they do not dominate the site and they are not visited or occupied by people during the calving season.

Site alterations on adjacent lands will have minor impacts on calving sites unless they are associated with developments which increase human activity in the area during the calving season. Construction on adjacent lands during the calving season has the potential to disturb moose and cause them to abandon the site.

Mitigation

In areas with high utilization of moose, islands and peninsulas should be checked in spring to see if they are used by moose as calving sites. If there is any evidence of use by moose then the site should be avoided if possible. Large-scale development may not be compatible with moose calving habitat.

Mitigation of the effects of development on calving sites will involve control of vegetation removal and human activity during the calving season. Mitigation may not be possible on small islands and peninsulas (i.e., < 0.5 ha, often prime calving sites) where site alteration is detectable from any point on the island or peninsula.

In large areas that are used for calving, construction should be concentrated in as small a portion of the habitat as possible (i.e. not spread throughout the calving site). Proponents should demonstrate that the area will remain viable moose calving habitat.

Human and dog activity must be severely limited at the site during the calving season (late May through the end of June).


Index #22 - Open Water Shoreline/Wetlands/Raptors/Rare or Specialized Habitat/Nesting and Foraging Habitat
Index # 22

Habitat Type:	Open Water Shoreline; Wetlands

Species Group: 	Raptors: Osprey, Bald Eagle [ENDANGERED]

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat:	Nesting and Foraging Habitat

Habitat Function and Composition

Ospreys and Bald Eagles use shoreline habitat for nesting and foraging. These species are fish-eating birds which forage in areas supporting abundant fish populations. Productive areas of open water or deep-water marshes are required to supply fish in the quantities needed by these birds to feed growing young. Nests are usually built in large trees near shore or over water. Artificial nesting structures may also be used. Nests are reused and become extremely large as new material (sticks, etc.) is added each year. Remoteness from human disturbances may be an important parameter in the selection of nest sites.

Osprey nests are almost always associated with large lakes or marshes and profitable foraging areas must be within 10 km of the nest. Most nests are along forested shorelines, on islands, or on structures over water. Most Ontario nests have been in mixed forest habitat, but nests also occurs in coniferous and deciduous stands. Occasionally, nests are situated in dry habitat 1 km or more from water. Dead coniferous trees are preferred for nesting; nests are usually at the top of the tree, but occasionally are in crotches. Less frequently, live or deciduous trees are used. Mature, isolated trees are usually selected as opposed to trees in a group. Most of Ontario's nests are 9 to 18 m from the ground, with extremes of 0.6 to 30 m. In the Lindsay area, osprey often nest on stumps in water. Nests are occasionally situated on hydro towers and poles, in heronries, and on artificial nesting structures. Almost all nests have an unobstructed view, and there is usually a tall perch nearby for the male. Nests are used year after year, sometimes for decades.

Most Bald Eagle nests are associated with large lakes, rarely small lakes or large rivers. Lakes with <5 km of shoreline are not used unless there is a larger lake within 1 km. This species shows a distinct preference for islands, but no preference for mixed, coniferous, or deciduous forest. Forest structure is important. Bald Eagles nest in mature or old-growth forest with discontinuous or open canopy, usually where there is 20 to 50% crown coverage. They show a preference for live trees and conifers in Ontario. In the southwest, sycamore and shagbark hickory are preferred; white pine is preferred in the northwest, although red pine is used; north of the range of white pine, trembling aspen is used almost exclusively. Shape, diameter, and structure of the nest tree are more important than species. Large trees (dbh 60 cm or greater) with crotches large enough to support the huge nest are essential. Most Ontario nests are 15 to 22 m from the ground, occasionally higher, in a crotch 1.5 to 6 m from the top of the tree. The nest tree must provide an unobstructed view and flight path in all directions. Nests are added to each year and may be used for decades. Alternate nests may also be built and be used in alternate years. These nests are usually close to each other, but may be as far apart as 5 km. Bald Eagles will occasionally use artificial nesting structures.

For large fish-eating birds like the Osprey and Bald Eagle, only water bodies or marshes which produce abundant fish populations or which are located near other bodies of water providing good fishing will function as nesting and foraging habitat. Both species require clear, productive, shallow water for fishing. The Osprey feeds primarily on bottom-feeding fish weighing 150 to 300 g which are caught by diving into water that is less than 1 m deep. Large lakes, rivers, and marshes with extensive shallow areas are required for foraging. The Bald Eagle prefers to hunt on large lakes with extensive shallow areas. A high percentage of fishing occurs where water is <6 m deep 50 m from shore. The Bald Eagle hunts from a perch, so the presence of suitable perches is essential. Preferred perches are on a shoreline near a productive feeding area and have an unobstructed view and flight path. Most perches are snags or large live trees with broken or dead crowns.

Potential Development Effects

Development which affects shoreline woodlands or marshes is likely to affect nesting Ospreys and Bald Eagles and possibly eagle roosting sites.

Building and other developments which result in a loss of forest cover along shorelines may impair or eliminate the site's function as a nesting area if mature trees are removed. The loss of trees already being used by raptors (nest sites, perches) may result in birds abandoning the area rather that nesting in other nearby trees. Also, there may be no other suitable trees available. Increases in human activity in the vicinity of active eagle (and to a lesser extent Osprey) nests may lead to their abandonment.

Development on lands adjacent to wetlands being used as nesting sites may have little impact on their function provided they do not increase human activity in the area. This depends on the distance of the development from the significant habitat and the types of activity that may occur.

Ospreys nesting in areas where humans are already tend to become habituated, but sudden disturbances such as occur on the holiday weekend in May often result in nest failure. Ospreys nesting in isolated areas are less tolerant of human activity. Bald Eagle sensitivity to disturbance may vary with the nesting cycle. Birds disturbed early may desert the nest, but those disturbed after incubation is well advanced tend to finish nesting. Some eagles become habituated, but most are susceptible to disturbance. Cottage lot development often results in a decline in nesting density and in eagles nesting farther than normal from the shoreline. The distance of nests from water increases with increasing cottage density. Low-density cottages may be tolerated at distances of 1.2 km, while nests tend to be 1.8 km away from medium- and high-density cottage developments. The farther away nests are from water, the more energy adults have to expend in supplying food to the nestlings, and reproductive success may decline. Birds displaced from nesting at the shoreline may not be able to find other suitable nest sites. Proponents should demonstrate that development will not displace Ospreys or Bald Eagles or demonstrate that they can successfully nest elsewhere.

Prime fishing areas for Osprey and Bald Eagles often are excellent angling areas. Use of traditional fishing areas by anglers may result in avoidance of these areas by the raptors, or they may be restricted in the times that the sites are available to them. Boating not only has the potential to disturb birds, the wakes that are created may make it difficult for birds to see into the water to capture prey. Any decline in fishing success affects rate of delivery of food to nestlings and reproductive success.

Any factors that affect fish productivity or water clarity will have adverse effects on Ospreys and Bald Eagles. This could include sedimentation or lake eutrophication. Wetlands are often the most productive fish habitat in lakes. They could be affected by changes in water levels or water-level fluctuations.

Mitigation

Mitigating the effects of development on shoreline raptor nesting habitat may not be possible if it is likely to impact fish populations or increase human activity within the offshore area or wetland. Large-scale development is unlikely to be compatible.

Development should be planned to minimize disturbance since both these species are intolerant of human disturbance while nesting and feeding. It may be necessary to ban motorboats on lakes or bays where eagles are nesting, and to a lesser extent, Ospreys, particularly if motor-boating will be a new activity. Nest sites should be posted as sanctuaries to prevent close approach of humans. Human activities such as motor-boating and canoeing should be restricted within 800 m of an eagle nest and 200 m of an Osprey nest. If there are only one or two key fishing areas on the lake for these bird species, thought should be given to making it a fish sanctuary or otherwise restricting boating and angling in the area.

Actual development should be set back even farther from nest sites unless it can be demonstrated that there will be no negative impacts on breeding birds or their reproductive success. Setbacks of 1 km for Bald Eagle nest sites and 500 m for Osprey nests are suggested. Development should not occur immediately adjacent to key feeding areas. These areas are less sensitive than nest sites, but are still critical to the birds. Setbacks from significant feeding areas of 500 m and 100 m are suggested for Bald Eagles and Osprey, respectively. However, if the development is fairly intensive, additional buffers may be required. For low-key developments such as a single cottage, proponents may be able to demonstrate that it is possible to develop closer than these guidelines without having adverse impacts.

Where Bald Eagle hunting habitat is involved, proponents should identify all perching and roosting trees. These trees should be protected and a buffer area established around them. The extent of buffer required is likely to vary depending on the nature of the perch site, and habitat that it overlooks, and the distance to the actual feeding area. Since a high proportion of food may be obtained by kleptoparasitism (stealing food from other bird species), not all perches may be situated near active fishing areas. Proponents could conduct field experiments to document distances at which birds flush from perches when the experimenters are engaged in different activities (boating, angling, walking, etc.). The results could be used to determine required setbacks. Care would be required to ensure that the experiments were not having negative impacts on the birds. Unless it can be demonstrated that closer activity will be tolerated, a setback of 300 m is recommended from hunting perches.

Developments or operations which will affect water clarity, fish production, or a decline in aquatic vegetation should be avoided. Appropriate sediment and nutrient controls will be required.

Ospreys, and occasionally Bald Eagles, can often be enticed to use an alternate (often manmade) nest site if an existing nest cannot be left unaffected. This should be considered only as a last resort. It should be demonstrated that birds successfully reproduce in the artificial structures before development proceeds.

The Bald Eagle is protected under the Ontario Endangered Species Act. No development is permitted in the significant portions of its habitat under Policy 2.3 of the Provincial Policy Statement. During the breeding season, significant habitat includes the nest site, feeding areas, and trees regularly used for perching. Any development application that involves Bald Eagle habitat will require input from the Ministry of Natural Resources.


Index #23 - Open Water Shoreline/Reptiles/Rare or Significant Habitat/Nesting Areas
Index # 23

Habitat Type: 	Open Water Shoreline

Species Group:  	Reptiles: turtles

Significant Wildlife Habitat Category: 	Rare or Significant Habitat

Functional Habitat:	Nesting Areas

Habitat Function and Composition

Many of Ontario’s turtles build nests along shoreline beaches.  They use these areas because they are located near water and since they are able to dig out nests in the light sand and gravel. These areas also afford good exposure to sun and allow faster development of eggs.

Sand and gravel beaches located near good turtle habitat (undisturbed shallow weedy areas of marshes, lakes, and rivers) are most frequently used.  Some beach strips are used by many turtles from the surrounding area each year. In areas where sand or gravel beach is in limited supply, isolated beaches become highly significant for the maintenance of viable turtle populations. Certain turtles may also nest at stream crossings and interfaces between creeks and marshes.

The exposed sand and gravel on beaches (or roadsides, railways, etc.) absorb heat from sunlight warming the substrate. This heat helps incubate the eggs, allowing them to hatch more quickly, leading to higher survival rates of young turtles.

For an area to function as a turtle-nesting area, it must provide sand and gravel that turtles are able to dig in. The beach must be wide and elevated enough that high water does not inundate nests. Predators like striped skunks, raccoons and others will dig out and eat eggs. Large wide beaches provide more nesting area and consequently reduce the odds that nests will be found by predators. Beaches adjacent to permanent water are preferred. When turtles must cross roads to nest or reach water, there is often high mortality.

Potential Development Effects

Shoreline development which includes site alterations to sand and gravel beaches have the greatest potential to affect turtle nesting sites. Development can reduce the amount of available habitat to the point where nests become very vulnerable to predation. Nests become easy to find because they are concentrated in a small area.

Construction of retaining walls and other structures which prevent access to the beach from water will eliminate the function of a beach as a turtle nesting site. Grading and filling can remove valuable nesting substrate. Excavation and dredging which alter shoreline hydrology resulting in waterlogged areas of once dry sand and gravel will destroy the function of the beach as a turtle-nesting area.

Increased human activity associated with development affects turtle nesting sites in two fundamental ways. Human activity on the beach during spring and early summer will discourage turtles from using the site. Raccoons and Ringed-billed Gulls often concentrate around areas of human activity foraging on refuse. These two species are serious predators of eggs and newly-hatched turtles.

Roads which separate water from backshore areas providing sand and gravel for nesting are hazards for turtles. Slow-moving turtles are often hit as they cross roads to get to nesting areas. Many newly-hatched turtles are killed by vehicles as they try to reach water. Grading of shoulders may dig up nests, and spraying emulsified oil on shoulders could affect egg viability.

Development on adjacent land is not expected to affect the function of beaches as nesting habitat provided it does not result in the release of contaminants into soil or water, increase human activity in the nesting area, or result in barriers to turtle movement patterns. However, humans may take some turtles as pets.

Mitigation

Mitigating the effects of development on turtle-nesting habitat involves ensuring that not all beach areas are developed or otherwise used by humans for recreation. Ideally, all beaches used for nesting by turtles would be left intact. If some development on the beach is necessary, the width of the beach should not be decreased, and spaces at least 30 m long should be left between individual cottages. It may be necessary to post the area as being off limits during critical periods or even fence it to reduce human usage. Any fencing should be designed so that it allows free passage of turtles, but inhibits access by raccoons and skunks.

On lakes or rivers where there is a limited supply of sand or gravel beach this provision takes on higher significance. Areas with known use should be protected. Reducing the size of suitable nesting areas may lead to a loss of function due to high nest predation.

In areas where the beach will be developed care should be taken to ensure that breakwalls or other structures do not isolate the beach from the water. Even a modest wall (i.e. < 20 cm high) may prevent turtles from accessing the beach.

Roads should be designed so that they are not barriers to turtles travelling between water and nesting areas. If this is not possible, suitable underpasses should be provided. Interpretative signage may also decrease the incidence of road mortality.

It may be possible to produce new or alternate nesting areas. This is, of course, a risky proposition since there is no guarantee that the newly-created site will be used by turtles. Proponents should demonstrate that this strategy works before development proceeds.


Index #24 - Open Water Shoreline/Colonially-Nesting Birds/Seasonal Concentration Area/Nesting Areas
Index # 24

Habitat Type:	Open Water Shoreline

Species Group: 	Colonially-Nesting Birds: American White Pelican [ENDANGERED], Double-crested Cormorant, Snow Goose, Ross's Goose, Ring-billed Gull, Herring Gull,  Caspian Tern [VULNERABLE], Common Tern, Arctic Tern

Significant Wildlife Habitat Category:	Seasonal Concentration Area

Functional Habitat: 	Nesting Areas

Habitat Function and Composition

Shorelines, and more often offshore islands, are preferred habitat for a number of different bird species which nest in colonies ranging in size from a few individuals to groups of hundreds or even thousands. These birds will tolerate close nesting by the same species due in part to the relative scarcity of suitable nesting habitat offering the safety and seclusion provided by water. Colonial nesting provides members a predator alert system. If there is invasion of predators, colony members will start a warning call or behaviour pattern that alerts all birds in the colony. Some species also swarm and “dive bomb” potential nest predators to drive them away. Nesting in colonies also reduces the probability of any one nest being destroyed by a predator. Older and more experienced birds usually nest in the centre of the colony while first-time nesters are usually forced to nest on the periphery on the colony. The water surrounding colonies serves as a barrier to many potential nest predators. Surrounding open water provides a productive food source for some colonially-nesting species.

The structure and composition of open water shoreline ecosystems which function as colonially-nesting areas varies among bird species. Below, a description of the key habitat requirements of the species in this guild is presented. No information is provided for American White Pelican, Snow Goose, Ross's Goose, or Arctic Tern. The pelican nests on only two lakes in northwestern Ontario where it is unlikely to receive any development pressure. It is, however, expanding so there is the potential that it will occur in other areas of the province in future. In addition, it is protected under the Endangered Species Act, so development is not permitted in the significant portions of its habitat under Policy 2.3 of the Provincial Policy Statement. The Ministry of Natural Resources must be contacted if any development proposals have the potential to affect pelican breeding areas. The two geese species and the Arctic Tern are restricted to the Hudson Bay Lowland where there is no development pressure.

Two species within this guild are expanding their populations considerably. The Double-crested Cormorant and Ring-billed Gull populations are very high in some areas of the province and, in some cases, they are having detrimental impacts on more sensitive species within this guild. The status of the local population may be taken into account when planning authorities are deciding which species are significant within their jurisdiction. It is rare that eradication of nesting sites for these species will be warranted, but it may not be desirable to allow populations to increase in some areas. These species are also protected under the Migratory Birds Convention Act and special permits are required to interfere with their nests.

Species	Habitat Characteristics
Double-crested Cormorant	Nesting colonies tend to be small in area, ranging from 0.4 to 1.2 ha; nesting may occur on bare soil or rocks, in tall dense vegetation, or in dead or living deciduous or coniferous trees; nesting colonies are often on southeastern slopes, as they provide protection from dominant winds; nests are usually mounds of twigs and sticks on the ground; tree nests are platforms of twigs; nests are used year after year; nest densities are high, approaching 1 nest/m2 in the centre of the colony; a good foraging area within 8 to 16 km is required; it eats mostly small and coarse fish obtained by diving in water <10 m deep over a substrate of rock and gravel
Ring-billed Gull	Nesting usually occurs on islands, but also on mainland peninsulas, isolated beaches, manmade spits, at landfill, etc.; on islands, it usually nests on bare granite or limestone, occasionally in areas of gravel or sparse grasses or weeds; at mainland sites, it usually nests among vegetation on gravel, sand, or rock; tends to avoid areas of dense vegetation and completely bare sandy soil; recently adapted to nesting on flat roofs; nests are a raised mound of grasses, plant stalks, aquatic vegetation, twigs, feathers, and fish bones; nests are usually very near water; nests are reused year after year; defends a territory of 1 to 4 m2; eats mostly earthworms and insects, as well as garbage, but also eats fish when they are readily available
Herring Gull	Nests mostly on rocky islands or small islets, occasionally on mainland in disturbed areas with limited vegetation; recently adapted to nesting on flat roofs; prefers islands 0.1 to 6 ha in area; usually nests very close to water; nests are raised mounds on flat ground built of vegetation, twigs, mud, feathers, and bones; rarely nests in trees; prefers sparsely-vegetated areas over bare areas, but avoids densely-vegetated areas; nests are reused; defends a territory of 9 to 460 m2; eats mostly fish, but is a very opportunistic feeder
Caspian Tern	Nests mostly on isolated, sparsely-vegetated islands or shoals, but also on manmade spits; recently adapted to nesting on manmade floating rafts; nests mostly on limestone, granite, gravel, or sand with no or very little vegetation; most nests are built of grass and dead vegetation; successful breeders usually return to the same colony, but there is much movement among colonies; stable colony sites may be used for decades or centuries; defends a territory of 1 to 2.5 m2; eats fish almost exclusively; nests are almost always immediately adjacent to a good food source
Common Tern	Nests mostly on sparsely-vegetated islands in large lakes, less frequently on shorelines and peninsulas, rarely in marshes; prefers islands 0.1 to 20 ha in area; most nests are on rock, sand, or gravel with sparse vegetation or among driftwood; recently adapted to nesting on manmade floating rafts; nests may be reused and birds tend to return to the same colony or even same nest, but may move as far as 60 km to another colony; defends a territory of 0.5 m2; eats fish almost exclusively; usually nests immediately adjacent to a good food source
Potential Development Effects

Excavation and building on portions of shorelines will have negative impacts on the function of the shoreline as a nesting area for colonially-nesting birds. These species are intolerant of human disturbance while nesting. Even developments affecting relatively small portions of undisturbed islands will cause birds to abandon the site as a nesting area.

Increased human activity during the nesting season (April through July) is not compatible with the functioning of shoreline areas as nesting habitat. Even infrequent disturbance of island sites may cause birds to abandon the site. Tree removal will destroy habitat for tree nesting species (i.e. cormorant).

Development on adjacent lands may have major effects on colonially-nesting birds owing to disturbance effects. Increased numbers of cottages and boats on lakes or rivers where there are nesting colonies may result in nesting disturbance. The nests of all of these species are occasionally destroyed by humans who perceive them to be a threat to their own fishing success. Mainland colonies are also highly susceptible to mammalian predators. Numbers of raccoons, skunks, cats, and dogs typically increase in association with development. A single nocturnal visit by a predator can result in the abandonment of the colony overnight and high mortality of eggs and chicks. Entire colonies have been deserted as a result of a single mammalian predator.

Mitigation

Development on small islands being used by birds as nesting areas is incompatible with colonially-nesting birds. Shoreline-colonial nesting sites should be avoided by development. These sites provide nesting areas for large populations of birds, all of which are sensitive to human disturbance. Large-scale development adjacent to mainland nesting colonies will probably result in the loss of the colony unless humans and predators can be excluded. Impacts on a colony may affect regional populations of the species involved.

Seasonal controls of human access to areas being used as nesting habitat will be required. Successful mitigation generally involves avoiding the nesting area for development and ensuring that there will be no access by humans or predators from adjacent developments during the breeding season.

Limited studies have been done on the distance that human activities affect breeding birds nesting in colonies. It is known, however, that birds react more negatively to walking humans than those in vehicles such as cars, motorboats, or canoes. Slow-moving watercraft, such as canoes, cause greater disturbance than faster-moving boats.

Some information is available for nesting Double-crested Cormorants in Florida. Nesting birds flushed from the nest at distances of 10 to 60 m from walking humans, 15 to 30 m from outboard motorboats, and 38 to 60 m from canoes. No information on flushing distances was found for other species in this guild. A minimum setback distance of 100 m for all human activities is suggested for species in this index, unless an Impact Assessment can demonstrate that nesting birds will tolerate closer activities.


Index #25 - Open Water Shoreline/Migrant Songbirds/Seasonal Concentration Areas/Migratory Route/Stopover Areas
Index # 25

Habitat Type:	Open Water Shoreline

Species Group: 	Migrant Songbirds

Significant Wildlife Habitat Category:	Seasonal Concentration Areas

Functional Habitat: 	Migratory Route/Stopover Areas

Habitat Function and Composition

Open water shorelines on large lakes, especially the Great Lakes, provide natural migratory routes and staging areas for migrating songbirds. Crossing large open bodies of water is hazardous for most small birds and many are reluctant to cross unless weather conditions are favourable (fair weather providing tail winds). Many birds opt to cross large bodies of water at narrow spots (i.e. Point Pelee, Wolf Island, etc.). Large numbers of migrating birds often stop to rest, feed and/or wait out poor weather in shoreline areas of the Great Lakes.

Many migrant birds follow shorelines as a means of navigating during migration. Small birds usually stop to feed and rest as they migrate. Shorelines along major migration routes which present a variety of bird habitat are important in ensuring that migrating birds are able to make their trips as efficiently as possible. These areas are also of value to migrating butterflies.

The structure and composition of habitats distributed along shoreline migration routes and particularly in traditional migration stopover areas are important to the maintenance of the area’s migration function. A diversity of habitat types ranging from open grasslands to large stands of mature forests is required along shoreline migration routes.

Geography may dictate the use of shoreline areas used as migration stopover areas more strongly than habitat structure and composition. This is not to say that habitat does not matter. It means that land forms and migration traditions result in large numbers of birds concentrating in shoreline areas waiting for favourable flying conditions before venturing across large water bodies or resting after crossing. Ideally, migration stopover areas should offer large areas of a variety of undisturbed habitat types. This configuration would provide a mix of habitat types for a diverse assemblage of migrating birds each having different habitat requirements. Under these conditions, many different species of birds can rest safely and forage profitably.

Ideally there should be a continuous supply of natural forest and open land within 5 km of the Great Lakes. This is particularly true for Lake Ontario and Lake Erie which have an east-west orientation. Forested habitat is especially important. It provides roosting areas, cover from predators, and food for most migrating species. Forest cover along watercourses is particularly valuable, as many birds require water while migrating. Forested ravines running north and south also allow birds to move leisurely during the day while supplementing their energy with food found within these habitats. Old-field areas and weedy fields are important to some seed-eating species such as sparrows and finches.

Potential Development Effects

Multi-lot developments have the potential to reduce or eliminate the function of an area as a migration route or stopover area owing to the relatively large areas impacted.

Tree cutting and other lot-clearing activities which reduce the density of foliage and simplify forest structure will affect the quality of habitat for migrating birds. Different species of birds forage at different heights within a forest. Some hunt for food on the ground, others forage in the shrub layer while others glean insects from high in the canopy. As vertical structure is lost, fewer species of forest birds are able to forage efficiently in the remaining habitat. Since large numbers of different species of birds concentrate in migration stopover areas it is important that the structural complexity of forests is maintained.

If the total amount of natural area (forest, old fields, wetlands) is reduced below a minimum amount, the areas may no longer be suitable for migrating birds, or they may be forced into smaller areas making them more vulnerable to predation and other mortality. Food resources may also become depleted if large numbers of birds are concentrated in small areas.

Development on adjacent land is not expected to affect the function of migration stopover areas provided that buildings erected do not act as a barrier to movement (e.g. high-rise office towers may cause considerable mortality among migrating birds).

Mitigation

Large natural areas with plenty of structure are very important to migrating birds. Therefore, development should be planned so that as much forest and undisturbed open habitat is maintained as possible. The area within 5 km of the Great Lakes (especially Ontario and Erie) is of great value to migrating birds. Planning authorities should try to maintain a continuous band of natural cover (forest and meadow lands) within 5 km of the Great Lakes.

Ideally, about 30% of habitat within 5 km of the lower Great Lakes shorelines should be in habitat suitable for migrant songbirds (forests, shrub thickets, old fields, wetlands). In some regions, less than this amount of suitable habitat currently exists. For developments within 5 km of the shorelines of lakes Erie and Ontario, the Impact Assessment should determine the importance of the area to migrating birds and whether the development will have negative impacts on them.

If lot-clearing activities are extensive within areas used by birds as migration stopover areas then mitigation may not be possible. Post-construction mitigation can include restoring the “naturalness” of vegetation by establishing areas of herbaceous plants, shrubs, and trees. Planting berry-producing trees and shrubs may be useful for sites that attract autumn migrants, and patches of native wildflowers will also be attractive to sparrows and finches. Tree and shrub cover is important in areas where spring migrants rest after crossing the lakes. Migrating birds tend not to be as affected by human disturbance as they are attracted to an area by food and cover.

Development should be planned so that construction and related human activity is concentrated in as small an area as possible. Large areas of continuous forest cover should be avoided for development or, if used, should only be developed at the edge rather than in the interior.


Index #26 - Open Water Shoreline/Raptors/Seasonal Concentration Area/Winter Roosts
Index # 26

Habitat Type: 	Open Water Shoreline

Species Group:  	Raptors: Bald Eagle [ENDANGERED]

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Winter Roosts

Habitat Function and Composition

Bald Eagles winter along shorelines of large bodies of water which provide areas of open water where fish are abundant and accessible. In recent years eagles have started to winter along the north shore of Lake Erie and they have done so for years along the St. Lawrence and Niagara rivers. Eagles roost in large trees growing in shoreline forest stands or on cliffs. The location of winter roosting sites changes within and among winters depending upon ice conditions and fish distribution, but the same general areas are used traditionally. In many cases, the same trees will be used year after year.

The availability of suitable roost sites is an important habitat feature in the recovery of this endangered species. Roosting sites function to provide protective cover within a reasonable distance from important winter feeding areas. Roosts may also double as hunting perches.

For an area to function as a winter roost site for Bald Eagles it must be located near areas of open water. However, eagles may also frequent deer yards where they may feed on carcasses. Highest concentrations of eagles will be found in areas offering the best fishing. An abundant supply of undisturbed mature trees or snags distributed evenly along shorelines is important to ensure that eagles can alter their winter distribution patterns depending upon ice conditions and fish distribution. Snags are preferred for perches and roosts as are tall trees with large horizontal branches. Suitable trees provide an unobstructed view and easy access from at least one side, but preferably from all sides. Perches are consistently taller than 7 m; immatures usually perch at heights of 7 to 15 m, while adults prefer perches and roosts taller than 15 m. Nocturnal roosts may be communal, and are sheltered from the wind and closely associated with water. Roosts and perches are in isolated areas where the birds will not be disturbed by humans.

Potential Development Effects

Shoreline development which results in the loss of significant numbers of mature trees or snags will affect the function of the area as a winter roost site for Bald Eagles. Even the loss of one or two key trees or snags could make the habitat unsuitable for roosting Bald Eagles. Due to this species' high intolerance of human activity, any type of development within 800 m to 1 km of roosting areas is likely to result in abandonment of the site.

Any development on adjacent lands (farther than 1 km from a winter roost) which increases human activity may result in abandonment of the area. Eagles tolerate moving vehicles, but tend to flush when a vehicle stops. They are very intolerant of pedestrians and may flush at distances as great as 300 m. Birds that are frequently disturbed will leave an area.

Mitigation

Development should avoid winter eagle roosting sites. Development should not occur within a kilometre of winter eagle roosting sites. Even at this distance, large-scale developments may be incompatible. Roads should not be constructed so that they pass within 300 m of roosting areas. Fencing or other means should be used to keep pedestrians from approaching within 300 m. Winter roosting areas can be maintained or enhanced by maintaining large trees and snags where possible, planting trees close to feeding sites, and curtailing human activity.

The Bald Eagle is an endangered species in Ontario, and development is not permitted within the significant portions of its habitat under Policy 2.3 of the Provincial Policy Statement. Winter roosting areas may be considered significant habitat for the Bald Eagle, depending upon factors such as the regularity of use and the number of birds involved. The Ministry of Natural Resources should be contacted for any development proposal within 2 km of an eagle winter roost.


Index #27 - Open Water Shoreline/Shorebirds/Seasonal Concentration Area/Migration stopover Areas
Index # 27

Habitat Type: 	Open Water Shoreline

Species Group:  	Shorebirds

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Migration Stopover Areas

Habitat Function and Composition

Migrating shorebirds follow shorelines or major river corridors as they move between winter and summer range. Many stop in traditionally-used areas to rest and feed before moving on. Some species use migration stopover areas much like “stepping stones” in a path between southern wintering areas and northern breeding habitat. Birds often move long distances between stopover areas. When they arrive in an area they need a safe place to rest and feed to replenish energy reserves needed to continue on. Large numbers may accumulate in stopover areas during poor flying weather. Once conditions improve birds leave and continue their journeys. Stopover areas must be large enough to supply adequate food supplies for the many birds using the area.

For an area to function as a migration stopover area for shorebirds it must provide a stretch of undisturbed shoreline in areas of relatively abundant food (insects, clams, snails, worms, etc.). Many areas are used traditionally and as such may have been selected for habitat features that are now gone or greatly reduced in abundance. Birds may continue to use  areas with less than ideal habitat composition and structure simply because they have always done so or have nowhere else to go. Some stopover areas are used primarily because of their geographic position with respect to migration routes. Species which use habitat in this way are vulnerable to development and natural catastrophes which affect the stopover areas that they use since they are reluctant to move to new areas. Rather, they continue to use denuded areas and their populations decline owing in part to increased mortality associated with use of low quality habitat.

Great Lakes shorelines provide some of the best shorebird stopover habitat because of their location along migration routes and since wave action maintains a large and productive beach where food is abundant. However, many inland lakes and marshes are also important shorebird migration stopover sites.

Most shorebirds have particular microhabitat requirements at migration stopover points. These include factors such as preferred foraging substrates, where they forage in relation to the water's edge, their diet, and roosting habitat. Some apparently minor alterations in habitat may make the area unsuitable for some species. The following table summarizes some of the habitat characteristics of migrating shorebirds. Only species that are likely to congregate in relatively large numbers in southern areas most susceptible to development pressure have been included. Species that stage predominantly on the Hudson Bay Lowland or that tend to travel singly or in very low numbers have been left out of the table. For the sake of completeness, some species that may prefer wet field to shorelines have been included, as some shorelines may have suitable habitat for them. Information on the timing of migration in the south is provided.

Species	Habitat Characteristics
Black-bellied Plover	Spring migration is from late April until early June; autumn migration is from late July to early November (males migrate first, then females, and finally juveniles); prefers shoreline mudflats and sand beaches, occasionally uses rocky shorelines; also uses wet pastures and ploughed fields; rarely ventures deeper than 30 cm into the water or farther than 3 m from shore; prefers emerged mudflats and substrate with aquatic vegetation or algae; eats fly and beetle larvae, earthworms, a variety of adult insects, and plant seeds
American Golden Plover	Spring migration is in the last half of May and birds often fly directly to the breeding grounds without stopping over; autumn migration is from mid August to the end of October; prefers drier areas, particularly rocky or gravelly areas; more likely to occur in upland habitats away from shorelines; at shorelines, forages near the water or in adjacent upland areas; rarely ventures into the water; eats insects, molluscs, and crustaceans
Semipalmated Plover	Spring migration is from mid April until the end of May; autumn migration is from mid July until mid October; prefers mud and sand substrates, but will use gravel and rocks; feeds at the water's edge or in backshore areas; almost never ventures into the water; feeds on algae and a wide variety of invertebrates
Greater Yellowlegs	Spring migration is from early April to early May; autumn migration is from mid July to late October; prefers shallow water over mud; avoids sand beaches; usually feeds in the water to a depth of 15 cm; eats aquatic insects, small fish, and amphibians
Lesser Yellowlegs	Spring migration is from early April to late May; autumn migration is from early July until mid November; has the same habitat preferences as the Greater Yellowlegs; forages in water mostly on small crustaceans, but will eat a wide variety of invertebrates
Ruddy Turnstone	Spring migration is in the last half of May and early June; autumn migration is from mid July until early October; prefers rocky shorelines and pebbly beaches; feeds above the shoreline, often about 10 m away; feeds by flipping over stones or by rooting like a pig; feeds mostly on invertebrates, but is very opportunistic
Sanderling	Spring migration is mostly in the last half of May; autumn migration is from mid July to late October; prefers sandy beaches; feeds at the shoreline, mostly on crustaceans and clams, but also on other invertebrates; roosts on logs or rocks higher up on the shoreline
Semipalmated Sandpiper	Spring migration is mostly in the last week of May and first week of June; autumn migration is from mid July to mid October; prefers beach pools and sheltered beaches; prefers mud and very fine silt with some algae; feeds mostly in water as deep as 2 cm; eats mostly aquatic invertebrates 4 to 6 mm long
Least Sandpiper	Spring migration is mostly in the last two weeks of May; autumn migration is from mid July until late September; prefers damp, soft substrate near the shoreline or well above it; rarely ventures into the water; feeds in areas with algae mats; eats aquatic insects, snails, and earthworms
White-rumped Sandpiper	Spring migration is in late May and early June; autumn migration is late July until early November; prefers mud, sand, and gravel substrates; roosts on high sandy beaches; feeds near the shoreline on aquatic invertebrates
Dunlin	Spring migration is mostly in the last half of May; autumn migration is from late September until early November; feeds at the shoreline in mud and sand; roosts above the water on logs and driftwood; eats aquatic and terrestrial insects and snails
Short-billed Dowitcher	Spring migration is mostly in May and early June; autumn migration is from late July until the end of September; avoids exposed beaches; prefers mudflats; forages at the water's edge or in water as deep as 30 cm; eats aquatic insects, molluscs, crustaceans, small fish, and plant seeds
Potential Development Effects

Development can have serious impacts on the function of areas as traditional migration stopover areas for shorebirds if sizable portions of the area used by birds or particular microhabitats used by certain species are altered.

Excavation, building and lot-clearing activities which affect the nearshore area and adjacent beach will affect shorebirds. Habitat quality is reduced when beach and nearshore area plant communities and structure are simplified, or if there is a reduction in the number of substrate types available. The loss of species and structural diversity reduces the availability of food and shelter for shorebirds.

Development on adjacent land is not expected to directly affect shorebird use of traditional stopover areas provided it does not result in an increase in human activity on beaches during peak migration periods.

Any development or operation that degrades water quality may have an effect on staging shorebirds. Water quality impairment can simplify the aquatic invertebrate community, resulting in less food for shorebirds, particularly for those species that specialize in feeding on certain groups of invertebrates.

Developments which occur on or very close to sand beaches have the potential to result in significant shoreline erosion. This may occur when structures are placed on the beach or even on sand dunes behind the beach, or when structures in the water interrupt coastal drift of sand. Developments considerable distances away may result in erosion, depending on current patterns in the lake.

Mitigation

The effects of developments like marinas and resorts which involve major changes to shoreline areas may not be able to be mitigated if site alterations occur in areas traditionally used by migrating shorebirds.  Traditional shorebird migration stopover areas should be avoided. The impacts of shoreline alteration and the resulting loss of function cannot be rehabilitated or compensated.

Development on adjacent land should be set back from the shoreline so that buildings and human activity are not visible from the beach. Trees may be planted to establish a visual barrier and reduce the noise associated with human activity, provided that trees will not impair shorebird habitat or discourage shorebird usage of the area. During peak migration periods of sensitive species, it may be necessary to implement measures to control human access to the shoreline.

Sediment control will be required during construction and appropriate stormwater management measures will have to be implemented to ensure that water quality is not impaired in the vicinity of the shoreline.

For developments that are close to the water's edge, it may be necessary to conduct coastal engineering studies to ensure that there will be no erosion of the beach.

It may be possible to design stormwater management ponds so they provide some shorebird stopover habitat (i.e. gentle slopes, sand or mud substrates). These habitats, however, in no way would compensate for the loss of an important natural area. Stormwater ponds should be additive as opposed to compensatory.

For significant shorebird stopover areas, the entire shoreline should be protected unless an Impact Assessment can demonstrate that development of portions of it will not have negative impacts on migrating shorebirds.


Index #28 - Open Water Shoreline/Woodland/Forest/white-tailed deer/Seasonal Concentration Area/Deer Yard
Index # 28

Habitat Type: 	Open Water Shoreline; Woodland/Forest

Species Group:  	white-tailed deer

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Deer Yard

Habitat Function and Composition

White-tailed deer migrate seasonally between summer and winter range. With the onset of snow accumulation, deer start to move into seasonal concentration areas called yards (typically in mid December). Movement to yards varies among individuals so deer do not move 'en masse' to or from yards. Deer remain in yards until snow melts in the spring (usually early April). By aggregating during winter, deer are able to establish and maintain a network of trails linking areas of food and cover. The coniferous forest cover available in yards provides protection from winds, hiding cover, and, by holding snow on their branches, conifers effectively reduce snow depth on the ground. An adequate supply of accessible woody browse is required in yard areas to provide food for deer throughout the winter. The concentration of deer during winter increases the chance of individuals surviving the effects of cold temperatures, deep snow, and predation. The same yards are used by deer and their descendants year after year. The knowledge of which yard to migrate to is passed on from mother to offspring. Individual deer yards draw animals from an area of surrounding landscape which is about 10 times larger than the yard itself. Therefore, activities which affect yard functions have impacts on deer abundance beyond the site level.

For an area to function as a deer yard it requires the following: 1) a history of use by deer; 2) absence of barriers to migration to and from the yard itself; 3) suitable areas of cover, food, and adjacent natural lands.

Deer yards have 3 basic habitat components: core areas; core feeding areas; and staging areas. Core and core feeding areas define the distribution patterns of deer during mid-winter (i.e. this is where they concentrate and spend most of the winter). As deer move into and out of yards they usually hold up temporarily (stage) in adjacent habitat. Deer often use staging areas located adjacent to yards for a few days or weeks prior to entering the yards depending on weather conditions. These staging areas are on lands surrounding core and core feeding areas (adjacent lands). Staging areas are usually associated with agricultural land offering food in the form of waste corn and grain, but they may also occur in oak stands when acorn crops are abundant. These areas are significant since they allow deer access to high quality foods before they are forced by severe weather to restrict their activities to core areas. Core areas are associated with conifer cover (forests composed of cedar, hemlock, spruce, white pine, etc. with > 60% canopy closure) and adjacent mixed or deciduous forest habitat. It is the mixed and deciduous forest habitat which provide feed in the form of woody browse. A preponderance of browse (deciduous species and cedar) in the understory of the core feeding areas is characteristic of a quality deer yard. In cottage country, the core areas of deer yards are often located along shorelines where mature conifer stands occur.

Potential Development Effects

Creation of multiple lots has the potential to disrupt yard functions totally if a significant proportion of yard area is affected. Because of the strong tradition deer show to using a given yard, deer will continue to migrate to the yard after development has occurred. It will take some time (i.e. > 2 to 5 years) before deer abandon the site. This does not mean that deer will simply establish a new yard somewhere else. What usually happens is that as deer are displaced by development and are forced to use poor quality habitat, they will succumb to a variety of mortality factors which the undisturbed yard protected deer from. Eventually deer numbers decline to a point where they are below that needed to establish and maintain an adequate trail network through snow. At that point, mortality rates climb and eventually there is a loss of traditional use of the area. This loss of function will affect deer over an area 10 times larger that the original yard. Development would have its greatest impact if it affected core and core feeding areas. In addition to reducing the amount of core yarding area available, development may also restrict the movement of deer along shorelines or other critical areas, reducing access to important parts of the yard.

On adjacent lands, development may affect the movement of deer into and out of the yard, and the other activities associated with staging. The activities of humans and their pets (particularly dogs) can have significant effects on deer especially during late winter when deer energy reserves are at low levels.

Single-lot development is not expected to have the degree of effect on yard function as subdivisions. Most severe impacts are expected when the lot is located in the core areas of the yard. Deer will usually abandon the impacted core area, and since core areas within the yard are limited, the overall carrying capacity of the yard (the number of deer it can sustain during an average winter) will be reduced. The cumulative effects of years of additional development in deer yards can grow to equal those of a subdivision development. Single-lot development on adjacent lands can affect how deer move to and from the yard. The greatest effect of adjacent land development will occur on sites where forest cover is adjacent to agricultural areas which offer deer access to high quality food. Deer commonly winter in forests among cottages along shorelines. Most cottages are vacant during winter and therefore disturbance is minimal. However, many cottages are becoming year round residences and as such present a greater impact on winter deer populations.

Any site alteration which reduces the area of forest cover or the food supply available to deer within the yard will have negative impacts on deer. The greatest impacts are anticipated in situations where core and core feeding areas are affected. Site alterations which isolate core areas from one another and/or from core feeding areas will result in deer abandoning the isolated habitat patch. Construction and site alterations on lands adjacent to the yard will have their greatest effect if they disrupt access by deer (i.e. road construction, industrial fencing, etc.). Deer are often killed on roads adjacent to yards during winter. This not only affects deer numbers but also presents a serious human safety hazard.

Mitigation

The effects of any development proposed for deer yards can be made less severe by directing activity away from core cover and core feeding areas, or areas of adjacent lands offering deer the opportunity to access abundant food supplies (i.e. agricultural crops).

Development proposed for core areas of yards measuring less than 10 km2 should be discouraged. Development in larger yards should be planned so that it does not disrupt more than about 15% of core area. This should be based upon 1998 conditions. Although one disruption of 15% of core wintering area may be acceptable in large yards, further development proposals cannot recommend an additional reduction in area of 15%. In many cases, loss of 15% of the core wintering area may not be feasible without having negative impacts. As a guideline, no more than 15% of core areas should be lost, and only in yards larger than 10 km2. Impact Assessments should determine the amount of core area that may be developed without having negative impacts on deer wintering habitat.

Development should not isolate the core areas. Planting of cover species (cedar, hemlock, spruce, white pine, etc.) could be planned to expand the core area away from the development. This should be seen as a long-term solution since it will take 20 to 40 years for the trees to develop the required canopy characteristics. (Note: it is very difficult to establish cedar and hemlock in deer yards without some form of temporary barrier since deer consume the trees before they grow out of their reach. Also, planted hemlock often does not do well even if it is not browsed by deer.)

Any development in core feeding areas should be planned so that the understory of the remaining woodland is left undisturbed (i.e. shrubs should not be removed). Browse supplies could be enhanced by opening up the tree canopy (i.e. reducing it below about 60% closure) in core feeding areas. The increase in browse may offset the loss of browse in the development area. Planting of browse would probably only increase overall browse supplies if the forest canopy is also opened up. Under a dense canopy, planted browse would not grow vigorously and would be quickly overbrowsed by deer (i.e. killed by browsing).

Human activity in either core or core feeding areas should be restricted during the winter since any movement by deer at this time incurs a relatively large investment of energy at a time when energy conservation is critical for their survival. Nature/recreation trails traversing these habitats should be closed while deer are yarding.


Index #29 - Open Water Shoreline/Migrant Butterflies/Seasonal Concentration Areas/Migratory Route/Stopover Areas
Index # 29

Habitat Type:	Open Water Shoreline

Species Group: 	Migrant Butterflies

Significant Wildlife Habitat Category:	Seasonal Concentration Areas

Functional Habitat: 	Migratory Route/Stopover Areas

Habitat Function and Composition

Open water shorelines on large lakes, especially the Great Lakes, provide natural migratory routes and staging areas for migrating butterflies. Crossing large open bodies of water is hazardous for butterflies. They need places to rest before and after crossing the Great Lakes.

The monarch butterfly [VULNERABLE] is the most regular migratory butterfly in Ontario. Adults migrate southward in autumn, congregating in large numbers along the northern shoreline of the Great Lakes, particularly Lake Erie. The adults overwinter predominantly in Mexico, and then return in the spring to breed.

Numerous other butterfly species wander northward from the United States in summer. Some species do this regularly, while others are sporadic visitors. All of these species benefit from having resting places and food resources along the shorelines of the lower Great Lakes. Other examples of species that may cross the Great Lakes are checkered skipper, fiery skipper, pipe vine swallowtail, checkered white, little sulphur, snout butterfly, variegated fritillary, painted lady, and the buckeye. These migrants from the south often establish breeding populations in the province that persist a few years after major incursions.

The structure and composition of habitats distributed along shoreline migration routes and particularly in traditional migration stopover areas are important to the maintenance of the area’s migration function. A diversity of habitat types ranging from open grasslands to forests is required. Most of the butterfly species that migrate prefer open habitats such as meadows, as these support food plant species for most of them. The monarch butterfly frequently rests in large numbers on trees, so the presence of shrubs and trees is important to it and some other butterfly species.

Geography may dictate the use of shoreline areas used as migration stopover areas more strongly than habitat structure and composition. Land forms and width of the adjacent lake may be important in defining butterfly staging areas. Ideally, migration stopover areas should offer large areas of a variety of undisturbed habitat types.

There should be a continuous supply of natural forest and open land within 5 km of the Great Lakes. This is particularly true for Lake Ontario and Lake Erie which have an east - west orientation. Old-field area and weedy fields are important to some butterfly species.

Potential Development Effects

Multi-lot developments have the potential to reduce or possibly eliminate the function of an area as a migration route or stopover area owing to the relatively large areas impacted.

Tree cutting and other lot-clearing activities which reduce the density of foliage and simplify forest structure may affect the quality of the area for migrating butterflies. Even more important to butterflies is the continued existence of old-field habitats. Conversion of old fields to residential development will greatly reduce or eliminate the function of the area as a butterfly concentration site.

Development on adjacent land is not expected to affect the function of migration stopover areas.

Mitigation

Development should be planned so that as much forest and undisturbed open habitat is maintained as possible. The area within 5 km of the Great Lakes (especially Ontario and Erie) are of great value to migrating butterflies. Planning authorities should try to maintain a continuous band of natural cover (forest and meadow lands) within 5 km of the Great Lakes.

If lot-clearing activities are extensive within areas used by butterflies as migration stopover areas then mitigation may not be possible. Post-construction mitigation can include restoring the “naturalness” of vegetation by establishing areas of herbaceous plants, shrubs, and trees. Planting patches of wildflowers will be attractive to migrating butterflies. Once developments mature, flower gardens may provide some habitat for migrating butterflies.


Index #30 - Open Water Shoreline/Prairie/Alvar/Savannah/Insects/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 30

Habitat Type: 	Open Water Shoreline; Prairie/Alvar/Savannah

Species Group:  	Insects: frosted elfin butterfly [ENDANGERED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Frosted elfin butterflies tend to be only locally common in small isolated populations. Populations are established in open oak woodlands, woodland edges, and old fields, but pine-oak savannahs seem to be preferred. In addition to the general habitat characteristics, there must be nearby populations of their host plants.

Adult butterflies emerge in early spring. Eggs are laid on the growing tips of host plants. Caterpillars burrow into flowers and feed on the flowers and developing pods. Host plants are legumes with inflated pods.

The fact that frosted elfins exist in small localized populations is significant. These small populations are prone to local extinctions. Areas of suitable habitat are re-colonized from surrounding sub-populations. In this light, finding areas with suitable habitat which contains no frosted elfins is not surprising. In time these patches of habitat may be re-colonized but only if patches of suitable habitat are protected (i.e. whether inhabited or not).

For an area to function as frosted elfin habitat it must provide relatively large populations of their host plants including wild indigo (Baptisia tincoria), lupine (Lupinus perennis), false indigo (Baptisia australis), and rattlebox (Crotalaria sagittalis). These plants grow in dry sandy soils. Beach dunes, pine barrens and pine-oak savannahs are preferred habitats.

The area of suitable habitat may be critical to the frosted elfin and its host plants. How much area is required will depend on factors such as whether the population is isolated or close to other populations and the existing population size. Isolated populations will require larger areas of suitable habitat in order to maintain genetically viable populations. It is generally acknowledged that approximately 500 breeding adults are required to prevent genetic drift (i.e. gradual movement toward being a distinct subspecies or even species) and 50 are required to prevent inbreeding (which usually results in rapid extirpation of the species). For isolated populations, the suitable habitat must be large enough to maintain a viable population. Where immigration from adjacent areas may occur on a regular basis, a smaller area may suffice. One important consideration is that all of the frosted elfin’s host plant species are also rare and have disjunct populations. Therefore, it is important that habitat area is large enough to support viable populations of these species as well.

Potential Development Effects

Development in areas of pine barrens, pine-oak savannahs, beach dunes or other sandy habitats with natural legume populations will affect frosted elfin habitat.

Excavation and construction which eliminates host plant populations will destroy the function of the area for frosted elfins.

Development on adjacent land is not expected to impact frosted elfin habitat provided that people do not trample, pick, or otherwise destroy their host plants.

Another lupine (Lupinus polyphyllus) is native to western North America, but is widely planted on gardens in Ontario. It readily becomes established in roadsides and other disturbed areas. It has not been documented as hybridizing with Lupinus perennis but it could possibly spread from gardens and crowd out the native species. It is unknown if frosted elfins will use the garden lupine, and if reproduction will be successful if they do.

Large-scale developments may result in closing of deer hunting seasons. This may result in a local build-up of the deer population. Deer are known to graze on the host plants of the frosted elfin, and this could result in a degradation in habitat.

Mitigation

Mitigating the effects of development on frosted elfin populations may not be possible if host plant populations are affected. Attempts to establish host plant populations may be successful provided that nearby areas of suitable growing conditions are available.

Development should be designed to avoid areas of frosted elfin habitat and provide a suitable setback to protect prime areas. For any development proposed within frosted elfin habitat or areas where its host plants occur, the proponent should demonstrate that viable populations of the host plants and frosted elfins will remain. In the case of endangered and threatened species, it is not adequate to demonstrate that some will remain; it must be demonstrated that populations will not decline as a result of the development.

Human usage of areas supporting host plants should be restricted. Motorized vehicles, such as dirt bikes, should be prohibited in areas where host plants are growing. Picking flowers should also be prohibited.

The frosted elfin is protected under the Ontario Endangered Species Act. Development is not permitted in the significant portions of its habitat under Policy 2.3 of the Provincial Policy Statement. Significant habitat is predominantly areas supporting any of the host plants, but other, site-specific factors may be important. Any development that has a potential to affect frosted elfin habitat should be referred to the Ministry of Natural Resources.


Index #31 - Prairie/Alvar/Savannah/Prairie/Alvar/Savannah Birds/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 31

Habitat Type: 	Prairie/Alvar/Savannah

Species Group:  	Prairie/Alvar/Savannah Birds: Northern Harrier, Sharp-tailed Grouse, Northern Bobwhite [ENDANGERED], Upland Sandpiper, Short-eared Owl [VULNERABLE], Red-headed Woodpecker [VULNERABLE], Loggerhead Shrike [ENDANGERED], Prairie Warbler VULNERABLE], Dickcissel, Lark Sparrow, Henslow's Sparrow [ENDANGERED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

A number of Ontario’s birds at risk require areas of relatively large, open grassland, alvar, or oak savannah. These areas provide their food, cover and nesting sites.  Other species nesting in these habitats may not require extensive areas, but have very specific habitat requirements, which limit their distribution. Many of these species also occur in field and meadow habitat, and are also covered in that index.

The primary requirements of these open-country birds are highly variable, but they represent a guild because they either require extensive areas of open habitat or have very specific habitat requirements. The following table outlines the general habitat requirements of prairie, alvar, and savannah birds of conservation concern:

Species	Habitat Characteristics
Northern Harrier	Prefers large, open fields with minimal shrub or tree coverage; seems to prefer open areas that are 30 ha in area or larger, but occasionally nests in smaller habitat patches; also nests in marshes, bogs, and fens; in fields, grass cover taller than 50 cm is preferred and the nest is often situated on a small knoll
Sharp-tailed Grouse	Nests in grasslands, on alvars, on bogs and fens, and in large clearcuts in extensive forests; prefers undisturbed grasslands with scattered shrub areas; males display communally at a lek; leks are open and slightly elevated, with low, sparse vegetation about 10 cm tall; typical leks are 70% grass, 15% forbs, 15% bare ground with a trace of shrubs; leks where grass cover falls below 60% or shrub cover increases to 20% are usually abandoned; leks usually have dense escape cover of tall grasses with intermittent shrubs for 500 m around them; nests are in open grass, usually where the residual vegetation has not been disturbed for at least 4 years; has a large home range of 500 to 600 ha; open habitat in extensive forest should be at least 2.5 km2
Northern Bobwhite	Requires grassy areas for nesting, shrubby areas for escape cover, and croplands for feeding; optimum areas have soils about 50% exposed, with the remaining areas containing upright herbs and shrubs; optimum habitat mix appears to be 30 to 40% grassland in 2- to 4-ha parcels, 40 to 60% cropland in 0.4- to 2-ha parcels, 5 to 20% shrubland in 0.1- to 0.4- ha parcels, 5 to 40% cropland in 2- to 8-ha parcels; avoids the interior of forests, large fields or prairies; very sedentary, often spending its entire lifetime within an area of 50 ha
Upland Sandpiper	Nests in old fields, hayfields, pastures, and at airports; may have originally been associated with short-grass prairie, also occurs on alvars; appears to require about 25 ha of open habitat; prefers uniform grass cover 15 to 30 cm in height, avoids areas where grass height exceeds 60 cm; presence of residual vegetation from previous years is important; needs perches for displaying such as fenceposts
Red-headed Woodpecker	Preferred habitat is oak savannah; optimum habitat is widely-spaced mature oak or hickory trees with an understory of grasses; may also nest in orchards, at woodlot and swamp edges, areas where large trees are stressed and dying, and in residential areas; may also nest in grazed fields with scattered large trees; avoids areas where there is extensive shrub or sapling growth; avoids large forests and landscapes that are extensively forested; nests in cavities in trees
Short-eared Owl	Prefers grasslands of various heights, densities and species compositions; also nests in bogs, fens, and marshes and on extensive sand dunes; appears to require about 75 to 100 ha of contiguous open habitat; nests tend to be in grass 30 to 50 cm tall, occasionally in vegetation as tall as 1 m; nests are often on knolls elevated 1 or 2 m above the remainder of the field
Loggerhead Shrike	Requires open fields of short grass and herbaceous plants with scattered shrubs or small trees (hawthorn or red cedar); uses marginal farmland, lightly-grazed pastures, and alvars; nearby wetland habitat may be important; probably needs at least 25 ha of suitable habitat; it appears to require landscapes where where at least 10% of the habitat is suitable for nesting or hunting
Prairie Warbler	Prefers dry fields or rocky barrens with abundant shrubby vegetation; pine/oak/juniper shrublands are often used as are extensive sand dunes; common juniper is the preferred nesting cover
Dickcissel	May have originally been associated with tallgrass prairie; nests in clover and alfalfa hayfields, undisturbed grasslands, old fields, and pastures; prefers heavily-vegetated fields with tall grass and herbaceous plants at least 50 cm tall; needs taller herbaceous vegetation or scattered trees and shrubs for singing and perching; dense litter 5 to 8 cm deep is preferred; will nest in habitats as small as 1 to 10 ha
Lark Sparrow	Prefers disturbed, open fields with short vegetation (? 15 cm), large amounts of bare ground with scattered boulders, trees, or shrubs that can be used as singing perches; often found in association with sandy soils and pine barrens; needs a minimum of 10 ha of suitable habitat
Henslow’s Sparrow	Originally associated with tall-grass prairie; nests in heavily-vegetated fields dominated by grass; prefers grass 1 m tall or more, but will use areas where grass is a short as 25 cm; tends to avoid fields where shrub coverage is much greater than 1%; tall, sturdy, herbaceous vegetation stalks are necessary for perching (common mullein, evening-primrose); low-lying (moist) fallow fields with an accumulation of dead plant material provide the highest quality habitat; long-term populations are associated with fields 40 ha in area or larger
Potential Development Effects

Species within this guild are considerably at risk because the habitat that they depend on is generally considered wasteland with limited ecological value. These habitats are often considered prime development areas, or planted to trees. Most of these species are experiencing declines.

Development which affects habitat for any of these bird species will affect the use of this significant wildlife habitat. Some of the species within this guild are threatened or endangered in Ontario: Northern Bobwhite, Loggerhead Shrike, and Henslow's Sparrow. The Ministry of Natural Resources must be consulted for any development proposal that may affect these species. Policy 2.3 of the Provincial Policy Statement requires that no development occurs in the significant portion of the habitats of threatened and endangered species. Other species are considered vulnerable, and the guidelines for the PPS suggest that, at a minimum, the best examples of habitat for vulnerable species should be maintained.

Excavation or construction which reduces the amount of suitable habitat will affect the number of birds which can use the area for breeding. Most birds are territorial during the nesting season and must retain a large enough area to forage and provide for their developing offspring.  Reductions in the amount of habitat will translate into the loss of nesting territories or a reduction in the amount of food available to birds using the restricted habitat area. Loss of suitable habitat is particularly critical to area-sensitive species that require a large patch of suitable habitat. Decreasing the amount of suitable habitat below a species' threshold may result in its abandoning the area. For example, reducing the area of suitable habitat from 150 ha to 50 ha will reduce the number of breeding pairs of species that are not particularly area sensitive, but may result in the loss of breeding Short-eared Owls. For some species, the amount of suitable habitat within the landscape is critical. Even loss of suitable habitat that is not directly inhabited may affect certain species such as the Sharp-tailed Grouse, Loggerhead Shrike, and Red-headed Woodpecker.

Site alterations which change the composition or structure (i.e. establishing lawns, etc.) or which result in the conversion of open areas to forest (i.e. tree planting or prevention of fire or grazing which once kept the area open) will have negative impacts on the function of the area for prairie/alvar/savannah birds. The above table demonstrates that many of these species have very specific microhabitat requirements; any changes in these will be detrimental.

Residential developments which result in there being many free-ranging pets (cats and dogs) will affect nest success by introducing significant predation to the area. Cats are also significant predators for prey for species such as Northern Harrier, Short-eared Owl, and Loggerhead Shrike. Shrikes are often killed on roads.

The two raptor species in this guild are susceptible to human disturbance. Human incursion into their nesting habitat may result in nest abandonment, or predators may follow human trails to find nests.

The Northern Bobwhite is particularly at risk because it requires several different habitat types in close proximity and it is very sedentary. Thus, the loss of any critical habitat component may result in the extirpation of a local population.

The Sharp-tailed Grouse is also at risk to development because of the extensive open areas that it requires, the fact that it displays communally in a very specific habitat, and that nests are in vegetation that has not been disturbed for a number of years.

Many of the species in this group nest on the ground and have very specific soil moisture requirements. Development which results in fields becoming drier or wetter may result in abandonment of the area by the species of concern.

Mitigation

Development should not reduce the amount of suitable habitat below the threshold size required by any area-sensitive species that occur in the area. Generally, if the amount of habitat that remains is large enough to support the most sensitive species, all other species should be protected provided that their microhabitat requirements are not lost. Lawns and back yards should not be considered part of the total area that is suitable for grassland-type bird species.

Impact Assessments should address drainage, habitat structure, and human and pet usage. Stormwater management studies and, in some cases, hydrogeological studies, will be required to determine if changes in grassland moisture regimes will occur. If changes may occur, then impacts on vegetation composition and structure should be determined along with ramifications on significant grassland and shrubland species.

Even if drainage patterns and most of the grassland/shrubland is maintained, management (or lack of intervention) may be required. Landowners may consider an adjacent old field to be a weedy eyesore. The temptation to plant the area in trees or mowing it must be averted. Interpretational signs or other educational techniques should be employed so that residents understand that they are living adjacent to significant species habitat and species. However, the reality is that interpretation often does not work.

It may be possible to create suitable habitat for some of these species of concern. If this is being done as compensation, the proponent must demonstrate first that the new habitat is being used successfully by the desired species.


Index #32 - Wetlands/Open Water Shoreline/Waterfowl/Seasonal Concentration Areas/Moulting Areas
Index # 32

Habitat Type:	Wetlands; Open Water Shoreline

Species Group: 	Waterfowl: ducks, geese

Significant Wildlife Habitat Category:	Seasonal Concentration Areas

Functional Habitat:	Moulting Areas

Habitat Function and Composition

During the breeding season, adult waterfowl undergo a complete moult which renders them flightless for a period of three to six weeks, depending on the species. Generally, larger species are flightless for longer periods of time. Flightless waterfowl are highly vulnerable to disturbance and predation during this time.

Some waterfowl species moult solitarily on or adjacent to the breeding area. Others, however, take what is termed moult migrations, and may travel considerable distances to traditional moulting areas. In between these two extremes, some species move to larger wetlands or water bodies near the breeding areas for the moulting period.

Drakes of many of the duck species abandon the female, flock together, and start their moult a full month in advance of females. During this period, many males lose their breeding plumage and take on an eclipse plumage that is often similar to that of the female.

There may be differences in the moulting habits of breeding versus non-breeding birds. This is particularly true for the Giant Canada Goose, which is generally considered a non-migratory bird in Ontario. Birds that are not mature enough to breed undergo a moult migration. They fly from southern Ontario to the Hudson Bay Lowland to moult. This is thought to be in response to a desire to be in an isolated area where there are few predators and little chance of disturbance. Breeding Giant Canada Geese do not have time to fly north to moult after they have raised their brood, so they spend the moulting period near the breeding area.

The moulting period is an extremely stressful time for waterfowl species. In that birds cannot fly during this period, the moulting habitat must provide everything that they require during this period. This includes food, shelter, water, suitable loafing or resting areas, and protection from disturbance.

For some species, moulting areas are traditional sites that are used year after year. Critical sites may provide moulting habitat for a variety of species, and birds may travel several kilometres, or even several hundred kilometres, to reach these areas. In some places, hundreds or thousands of moulting birds may congregate. Loss of traditional moulting sites has the potential to affect regional populations of some waterfowl species.

Waterfowl use a variety of wetlands and open water habitats as moulting areas. Larger wetlands and water bodies seem to be preferred, probably because birds can get far away from the shoreline and be safe from predators.

The various waterfowl species have different habitat requirements while they are moulting. The following table summarizes these habitat characteristics. Information has only been provided for those species that are known to congregate during the moult. However, it must be emphasized that moulting waterfowl can be very inconspicuous, and more waterfowl species may congregate than is currently known. Information is not provided for those species that nest and moult in the extreme northern portions of the province where they are unlikely to be affected by development.

Species	Habitat Characteristics
Canada Goose	The flightless period is 32 to 40 days; it prefers to moult on large marshes or even lakes; at night, it often roosts on the water far from the shore; when it must use smaller wetlands, it prefers those with a band of shoreline emergent shrubs where it can hide; sometimes it will use a complex of wetland ponds and kettles where it can move among the wetlands to obtain food or shelter; it also likes some areas where there is little to no tall shoreline vegetation so that it can go on shore without fear on having predators lurking in tall vegetation; it needs a good source of food immediately adjacent such as grain fields
Wood Duck	Extremely secretive during the moult, and very limited information is available; appears to use swamps and extensive marshes that are relatively inaccessible to humans; primary moulting habitats are emergents along lakeshores and watercourses, particularly wild rice, but also areas of dense willow or alder thickets; often moults in or near the brood areas, selecting the densest cover available; moult migrations may occur, but it does not congregate in large flocks
Green-winged Teal	Drakes desert the females shortly after initiation of incubation and undergo a moult migration; occasionally females will also undergo a moult migration; they congregate in large flocks, usually on large marshes or shallow lakes
American Black Duck	Limited information is available; males may congregate during the moult; in the south, it prefers marshes, but sedge ponds are used in the north
Mallard	Males congregate during the flightless period (3 to 4 weeks) and may be accompanied by females that have lost their brood; large marshes are inhabited during this period
Northern Shoveler	Drakes flock together on large water bodies during the moult; one of the most secretive of the dabbling ducks during the flightless period; highly dependent on emergent vegetation; rarely strays from emergents and remains in them all night
Gadwall	Males congregate in large marshes for the moult; dense vegetation, such as cattails are essential; hens may fly to the southern States to moult shortly after leaving the brood
American Wigeon	During the flightless period (~35 days), it inhabits very large lakes and marshes; stays well away from shore and usually associates with diving ducks; may fly several hundred kilometres to moulting sites
Ring-necked Duck	Concentrates on large, open marshes during the moult; appears to prefer marshes with emergent populations of bulrushes and sedges
Lesser Scaup	No information is available for Ontario birds, but it appears to moult on large lakes in western Canada
Potential Development Effects

Draining, dredging, excavating, filling portions of wetlands to establish development will have negative impacts on the function of the wetland as a waterfowl moulting area. This may result in direct habitat loss for these species. In addition, the smaller wetland basin that will remain is likely to be subject to higher water levels due to reduced storage. The deeper water is likely to reduce the extent of aquatic submergent and emergent vegetation, which is critical to many of these species. Most of the waterfowl species in this guild require large wetlands during the moult so that they are safe from predators and disturbance. If the wetland area is decreased, moulting waterfowl may no longer use the site.

Changes to water levels may result from adjacent development, and this may affect the distribution of aquatic vegetation in the wetland or lake. Changes in the ratio of emergent cover to open water may also affect habitat quality for many species. If significant areas of marshland vegetation are affected, then the marsh may cease to function as waterfowl moulting habitat.

Water levels may decline if development inhibits groundwater recharge, or if surface water is diverted away from the wetland. Declining water levels are likely to increase the amount of vegetation in the wetland and change the vegetation composition. Lower water levels may make the habitat unsuitable for species that prefer deeper, open water.

Water levels may increase if a significant portion of the wetland's watershed is hardened resulting in a higher percentage of precipitation being directed to the wetland. Diversion of water by development may also increase the watershed area. Higher water levels will result in less aquatic vegetation and more open water. This may make the habitat unsuitable for certain species, particularly those that prefer extensive stands of emergents, shoreline shrubs, or shallow water.

Development may also change the frequency, duration, and magnitude of water-level fluctuations. Unnatural water-level fluctuations may affect distribution and diversity of aquatic plants and favour invasion by species such as reed grass and purple loosestrife.

Water quality in the wetland may be altered as a result of runoff from the development or due to construction activities. Increases in turbidity as a result of higher sediment and nutrient loadings may reduce the depth that sunlight penetrates into the water column. This reduces the area of the wetland that is capable of supporting aquatic submergents. As water turbidity increases, the plant community becomes less diverse, and is dominated by aggressive, pollution-tolerant species. Invertebrate and fish populations also become less diverse. These factors reduce habitat quality for moulting waterfowl. Significant degradation of water quality can reduce the life of the wetland.

Development on adjacent lands may have major effects on moulting waterfowl owing to disturbance effects. Most of the species are sensitive to human activities; this is why some of them are restricted primarily to larger water bodies and wetlands. Where the wetland is a large water body, birds may be disturbed by boats.

Mitigation

If development is to occur in wetlands it may not be possible to mitigate its effects on the function of the remaining wetland as a significant waterfowl moulting area. Development must be planned to ensure that marsh area is not greatly reduced, particularly to the point where the marsh is incapable of supporting the most sensitive species present.

Development within a wetland will greatly affect hydrology and therefore plant communities within the wetland. Development will reduce the storage area of the wetland. If the same watershed is maintained, water levels are likely to increase, thereby reducing the extent of vegetation within the marsh. A water balance should be conducted for any development proposed within a wetland.

Adjacent land development can be benign provided care is taken to ensure that water levels or water quality do not change. Hydrological studies will be required to predict changes in water levels and the duration, magnitude, and frequency of water-level fluctuations. If the wetland receives groundwater inputs, it should be demonstrated that development will not alter the amount of groundwater reaching the wetland. Appropriate stormwater management will be required to ensure that an excess of sediments or nutrients does not reach the wetland. For large-scale developments, a water and nutrient balance may be required to demonstrate that there will be no impact on wetland functions.

For many species, it may be necessary to control human activities. For the most sensitive species, large-scale development near the moulting area may not be compatible. For the species that are most sensitive to disturbance, it may be necessary to limit use of the wetland by boaters and canoeists during the moulting season.


Index #33 - Wetlands/Reptiles/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 33

Habitat Type: 	Wetlands

Species Group:  	Reptiles: spotted turtle [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Spotted turtles inhabit a variety of wetlands including marshes, swamps, bogs, fens, ditches, and other areas of shallow, slow-moving water. These areas provide all the life requirements of food, cover, nesting habitat, and areas for hibernation (in bottom sediments and beneath the root mass in bogs). Because these turtles rely totally on one location for all their resources they are vulnerable to factors which affect water quality and vegetation composition and structure.

A variety of wetland types function as spotted turtle habitat. The key habitat requirements of the species are unpolluted, slow-moving shallow sources of permanent standing water contained in a basin with muddy substrate. Like other turtles, the spotted turtle requires a nearby source of sandy soil for nesting, but it also nests in sphagnum on rocks.

Potential Development Effects

Development which results in excavation, dredging, draining or filling of significant portions of wetlands which have abundant vegetation and muddy bottoms will affect spotted turtle habitat.

Changes to the hydrological function of a site can have major impacts on entire local spotted turtle populations, particularly if hibernacula are affected. Spotted turtles are gregarious and have high site fidelity to hibernacula. Alterations to an area that affects the microclimate of hibernacula can have adverse effects on populations. This species is often found in small wetlands. Minor changes to surface water flow can easily cause their habitat to dry up. If this occurs, the turtles will likely perish in the dry pond rather than move away in search of other suitable wetlands. Populations tend to be very small and isolated. Entire local populations can easily be eliminated.

Development on land adjacent to wetlands will affect the function of the area as spotted turtle habitat if it results in the drying of nearby wetlands or changes the microhabitat of hibernacula. Also, if sandy areas located near (i.e. < 100 m) the wetland are eliminated or become isolated by development or roads, critical nesting habitat will be lost. Increases in human activity in the area of the wetland are expected to negatively impact these turtles. They are intolerant of human activity, and spotted turtles are often taken as pets.

Contaminant runoff from adjacent developments (herbicides, pesticides, petroleum, sediments, excessive nutrients) can have major impacts on spotted turtles because they often use small wetland areas which have little capacity to dilute pollutants. These chemicals can also affect wetland vegetation and the overall quality of spotted turtle habitat. Spotted turtles feed mostly on aquatic insects and other invertebrates, but also occasionally on tadpoles and small fish. The abundance and distribution of its prey can be adversely affected by degradation of water quality and changes to the structure and composition of the vegetation.

Mitigation

Mitigation of the effects of development on spotted turtle habitat involves considering the fate of small wetland areas which occur on the site. Because these turtles often use small wetlands as preferred habitat, their populations are vulnerable to total elimination. These areas are often considered too small to be highly-valued wetlands. If spotted turtles are found on a development site then care must be taken to ensure that their wetlands are not filled or dried out as a result of site alterations. Suitable sediment controls will have to be implemented and maintained during construction to ensure that sediments do not reach spotted turtle habitat.

Care must be taken to ensure that the wetland does not become contaminated by surface water containing pesticides, etc. Small ponds and ditches are particularly vulnerable to contamination owing to their low capacity to dilute pollutants. Appropriate stormwater management facilities will be have to be constructed and operated according to an approved manual.

Development should be situated where it does not isolate nesting sites from the wetland areas that are usually inhabited. Roads should also not be constructed where they form a barrier to turtles moving among critical habitats. The potential for gravel along new roads being used as nesting habitat with a resultant increase in road mortality should be considered in Impact Assessments.

Planning should ensure that nearby areas of sandy soil are left intact as nesting habitat. It may be possible to construct suitable nesting habitat if natural sites cannot be avoided. The new nesting site should be constructed before the old area is developed to ensure that the turtles actually use the newly-constructed nesting habitat. If they do not use the manmade habitat then the existing nesting habitat must be left undeveloped.

However, it is probably even more important to identify and protect hibernacula. Spotted turtle populations are generally difficult to identify. They usually bask for several weeks and are most apparent in spring after they emerge from hibernation, and just before entering hibernation in autumn. The rest of the year, they may be active but spend a lot of time submerged (feeding/breeding) or concealed amongst vegetation. During periods of drought, they may aestivate.


Index #34 - Wetlands/Reptiles/Habitat of Species of Conservation Concern/Hibernacula
Index # 34

Habitat Type: 	Wetlands

Species Group:  	Reptiles: eastern massasauga rattlesnake [THREATENED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Hibernacula

Habitat Function and Composition

Massasauga rattlesnakes survive the winter by hibernating underground in sites which reduce temperature variations. Most massasauga migrate from upland old field or woodland habitats to wetlands in the autumn to find suitable sites for hibernation.  Entrance to subterranean hibernacula is gained via small mammal burrows, along the roots of rotting stumps and through rock crevices, etc. Massasaugas generally hibernate alone rather than in large aggregations like some other snakes.  These snakes spend considerable time during the spring foraging in and around wetlands before moving back to their summer home ranges.

A variety of wetland types function as hibernation sites for Massasauga rattlesnakes. However, wetlands providing areas of sedges and other low-growing vegetation seem to be preferred. Consequently, fens and bogs may be more attractive to hibernating massasaugas than marshes or swamps. Sedge meadows provide suitable spring foraging sites.

Potential Development Effects

Development which results in the draining or filling of portions of wetlands which have sedges, grasses, or rushes dominating the vegetation community will affect massasauga rattlesnake hibernation areas.

Lot-clearing activities which remove patches of natural, low-growing vegetation will reduce foraging opportunities for massasaugas during spring. If this activity is extensive and small mammal populations frequenting these habitats are greatly reduced, then the number of massasaugas that can winter in the area will be reduced. Spring hunting opportunities in and around the wetland are important in maintaining wetland function as a hibernation site. Lot clearing which removes structure like downed woody debris, stumps, rocks, etc., reduces the availability of daytime resting sites for snakes (important in spring particularly) and negatively affects prey populations.

Development in the vicinity of wetlands functioning as rattlesnake hibernating habitat presents considerable risk to these snakes. Humans kill significant numbers of massasaugas intentionally or by accident as the snakes cross roads or are discovered hiding.

Development on land adjacent to wetlands may also affect the function of the area as a hibernation site if it results in the isolation of the wetland from surrounding upland habitat. Roads, cottage lots, and other structures which must be crossed while snakes move in and out of the wetland area may act as barriers, or cause high rates of mortality. Increased mortality in populations may affect their long-term viability.

Mitigation

It is unlikely that many rattlesnake hibernacula will be found during site inventory. Therefore, when identifying significant wildlife habitat, most likely areas should be delineated based on habitat features and the presence of snakes during early spring when they emerge. These areas should be protected. Also, movement corridors that are used by snakes as they travel from summer range to their hibernacula should be protected.  All attempts should be made to prevent development in or adjacent to areas functioning as hibernation sites for rattlesnakes. People and rattlesnakes are basically incompatible. Large-scale development near massasauga habitat is likely to result in a significant decline in snakes or even local extirpation.

Mitigating the effects of development on massasauga rattlesnake hibernation areas involves protection of areas of sedges and other low herbaceous plants.

Tree-cutting and lot-clearing activities in the wetland fringe should be controlled so that the structural complexity of the ground is either retained or enhanced. This will effectively increase daytime rest site availability as well as prey populations.

If residential development is to occur near wetlands functioning as hibernation areas there should be a public education program put in place to inform residents on basic rattlesnake biology and what to do in the event of an encounter. This, however, may be of limited effectiveness because of the inherent fear that many humans have of snakes, particularly those that are poisonous.

Roads should not be built so that they run parallel to, or encircle the wetland. Signage (“brake for snakes”, etc.) warning motorists that snakes are likely to be crossing the roadway may help reduce road mortality. However, some individuals will go out of their way to run over a snake.

Clustering of development to protect as much natural habitat as possible may reduce impacts on massasauga populations.

The eastern massasauga is a threatened species and, therefore, development is not permitted in the significant portions of its habitat (Policy 2.3 of the Provincial Policy Statement). Portions of the habitat that should be considered significant include hibernacula, nesting areas, foraging areas, courtship areas, and corridors among these key areas.


Index #35 - Wetlands/Marsh birds/Species of Conservation Concern/Breeding Habitat
Index # 35

Habitat Type:	Wetlands

Species Group: 	Marsh birds: Pied-billed Grebe, Red-necked Grebe, American Bittern, Least Bittern [VULNERABLE], Great Egret, Black-crowned Night-Heron, Redhead, Ruddy Duck, Yellow Rail, King Rail [ENDANGERED], Virginia Rail, Sora, Common Moorhen, American Coot, Sandhill Crane, Wilson's Phalarope, Little Gull, Forster’s Tern, Black Tern [VULNERABLE], Yellow-headed Blackbird

Significant Wildlife Habitat Category:	Species of Conservation Concern

Functional Habitat: 	Breeding Habitat

Habitat Function and Composition

This index deals primarily with species that nest in marshes, one of the four wetland types that occurs in the province. Some species that are dependent on bogs or fens are included, but only if these species appear to be declining and occur in areas that may receive development pressure. Species that nest mostly in swamps are covered under the woodland/forest habitat, although these are also wetlands.

Marshes are the preferred habitat of many of Ontario’s birds. Some of these are at risk due to the continuing loss of wetland habitat in the province. Others face other limiting factors during migration and on their wintering grounds. Degradation or fragmentation of marshes has been detrimental to some species. The status and population trends of some of these species are not well understood, as many are difficult to detect. In some jurisdictions, certain of these species may be locally abundant but considered rare because they are seldom encountered.

This guild contains a diverse assemblage of species, each with specific habitat requirements. Development or management that is detrimental to one species may be advantageous to another. The following table summarizes the general habitat requirements of species in this guild.

Species	Habitat Characteristics
Pied-billed Grebe	Prefers marsh-lined ponds, lakes, and rivers, but also common on beaver ponds; usually nests in dense stands of cattails, bulrushes, bur-reeds, spike-rushes, or arrowheads; occasionally nests among emergent shrubs; prefers to nest in water depths of 30 to 100 cm; nest is a floating mass of aquatic vegetation; not area sensitive, frequently nesting on ponds on wetlands smaller than 2 ha, down to 0.2 ha
Red-necked Grebe	Nests on large, open expanses of marshes or water bodies with a medium density of emergents such as bulrushes, cattails, horsetails, or reed grass; prefers to nest in water 25 to 150 cm deep at a distance of 1 to 18 m from shore; the nest is usually a floating mound of aquatic vegetation; a minimum of 2 ha is required to support a pair, with most birds having a territory size of about 4 ha; generally associated with very large water bodies and marshes in Ontario
American Bittern	Nests mostly in marshes, but occasionally in bogs, fens, and old fields; nests are usually built in emergents such as cattails, bulrushes, and sedges in water as deep as 45 cm; usually nests in marshes 10 ha or larger, but occasionally in wetlands as small as 1 ha
Least Bittern	Prefers to nest in dense stands of cattails, but also nests in bulrushes, reed grass, horsetails, sedges, grasses, and shrubs; the nest is in emergents in shallow water as deep as 1 m; long-term populations appear to be associated with marshes 100 ha or larger, but it occasionally nests in wetlands as small as 1 ha
Great Egret	Nests in flooded timber and shrubs adjacent to wetlands; may also nest in bulrushes and on the ground, although this has not yet been documented in Ontario; most nests in trees are 4.5 to 9 m from the ground; may nest with Great Blue Herons, Cattle Egret, Green Heron, and Black-crowned Night-Heron
Black-crowned Night-Heron	Nests near water including flooded trees and shrub thickets over and adjacent to water; usually nests in deciduous species, occasionally conifers; rarely nests in emergent vegetation in marshes; most nests are 2 to 4 m above water, but they may be as low as 0.3 m
Redhead	Nests mostly in emergents in marshes, occasionally in bogs and fens; prefers areas with abundant emergents and open water with submergents; prefers bulrushes for nesting, but also uses cattails, sedges, and rushes; in Ontario, it is usually associated with very large marshes and water bodies; elsewhere, it may nest in wetlands as small as 5 ha
Ruddy Duck	In Ontario, nests in marshes; prefers cattails, bulrushes, and sedges; nests in water depths of 30 to 90 cm; associated with very large marshes in Ontario; elsewhere, usually nests in wetlands larger than 10 ha, but occasionally in marshes as small as 0.3 ha
Yellow Rail	Nests in large marshes and fens dominated by sedges or grasses; nests in damp areas or in water as deep as 10 cm; requires the presence of dead vegetation from previous years; nests on the ground at drier margins of wetlands; most Ontario nests have been in very large wetlands
King Rail	Nests in shallow marshes (<10 cm) of cattails, bulrushes, sedges, or grasses; prefers drier borders of wetlands and islands; nests are 10 to 50 cm above ground or water in emergents; usually nests in wetlands 200 ha or larger
Virginia Rail	Nests in dense vegetation in shallow water, including marshes, beaver ponds, ditches, and openings in swamps; preferred vegetation is cattails, bulrushes, sedges, or grasses; avoids areas without standing water; prefers water depths <10 cm but tolerates water as deep as 25 cm; may nest successfully in very small wetlands, but usually associated with marshes 1 ha or larger
Sora	Nests in marshes with emergents and shallow water, occasionally in damp meadows and bogs; wetland size and type of emergents are not important; prefers water depths of 8 to 20 cm, rarely to 40 cm; avoids areas without standing water; prefers wetland edges and interfaces between vegetation and open areas
Common Moorhen	Nests mostly in cattail marshes, but also among bulrushes, sedges, bur-reeds, sweet gale, arrowhead, and reed grass; prefers water 40 to 50 cm deep and an approximate 50:50 ratio of open water to emergents; most nests are among emergents, built of emergents, in water depths of 30 to 90 cm, and are 20 to 30 cm above water; appears to prefer small and medium-sized marshes to large ones
American Coot	Nests mostly in cattail marshes, but also uses bulrushes, sedges, bur-reeds, reed grass, and willow shrubs; prefers wetlands with a 50:50 ratio of emergents to open water; most nests are well concealed in emergents, are 15 to 30 cm over water averaging 50 to 70 cm deep, and are 1 to 7 m from open water; appears to be associated with very large marshes in Ontario, but elsewhere may nest on wetlands smaller than 1 ha
Sandhill Crane	Nests mostly in bogs and fens, but occasionally in marshes; vegetation type near the nest does not appear to be overly important; requires large wetlands, usually 200 to 400 ha in area, occasionally smaller; usually nests at least 1 km from any human activity
Wilson's Phalarope	Nests among grasses and sedges at the margins of wetlands or on islands; prefers grasses about 30 cm tall and avoids vegetation taller than 60 cm; the nest is usually near water (<15 m) in a dry location, but one Ontario nest was 45 m away from water; forages in shallow water or on mudflats in wetlands; more frequent in small wetlands than large ones; also nests at sewage lagoons
Little Gull	Nests in marshes associated with large water bodies such as the Great Lakes, occasionally on small ponds; nests are floating or semi-floating mats of aquatic vegetation, or they may be on muskrat houses; usually nests are in open water, occasionally among sedges or cattails; usually nests in water 20 to 70 cm deep
Forster’s Tern	Nests in deep-water, large marshes; prefers areas dominated by cattails or bulrushes; nests away from shore, with emergents around islands 0.1 to 1 ha in area being preferred; optimum distance from mainland where water is >50 cm deep is 1 to 3 km; seldom uses marshes smaller than 300 ha; nests are floating masses of aquatic vegetation or are on muskrat houses
Black Tern	Nests in marshes dominated by cattails, but also bulrush, sedge, and bur-reed marshes; prefers a 50:50 ratio of emergents to open water, but also nests in small openings within extensive emergents; rarely nests where water depths are <0.5 m; prefers water depths of about 1 m near the nest; the nest is a floating or anchored mass of aquatic vegetation; it is area-sensitive, rarely occurring in marshes smaller than 20 ha
Yellow-headed Blackbird	Nests in deep-water marshes, mostly among dense cattails but also in bulrushes; nests are attached to emergents; nests in small to large marshes
Potential Development Effects

Draining, dredging, excavation, or filling portions of wetlands to establish development will have negative impacts on the function of the wetland as a nesting area for marshland birds.

Changes to water levels as a result of development will affect distribution of emergent vegetation and, therefore, habitat for marsh-nesting birds. Cattails and other marsh plants are sensitive to water-level fluctuations and depths. As water levels change, so does the density of cattails and other vegetation. As water levels increase, the amount of emergent vegetation declines and the ratio of emergent vegetation to open water decreases. If water levels increase during the nesting season, nests situated near the water's surface may be flooded. As water levels decline, the areal extent of emergents increases as does the ratio of emergents to open water. Lower water level may expose some nests that were initially built over shallow water to become more vulnerable to predators, and the lack of open water may discourage some bird species from nesting. If water-levels fluctuate more than normally, this may flood or expose nests. It also stresses aquatic plant communities and may favour invasion by species such as purple loosestrife or reed grass. Because marsh birds have specific nest site vegetation density requirements, they will abandon sites when vegetation cover becomes too sparse or too dense. If significant areas of marshland vegetation are affected, then alternate nesting sites within the marsh may not exist. As a consequence the marsh may cease to function as nesting habitat for certain bird species of conservation concern.

It is important that marshes remain as large as possible. Loss of wetland area will result in there being fewer feeding and nesting areas for birds, or the remnant wetland may not be large enough to support area-sensitive species.

Development on adjacent lands may have major effects on nesting birds owing to impacts on marsh water levels or degradation of water quality. Discharge of sediments or high nutrient loadings to wetlands can effect the distribution of aquatic plants. Increased turbidity due to sediments or algae blooms decreases the depth that sunlight can penetrate the water in the wetland. This decreases the area that is capable of supporting submergent vegetation. As turbidity increases, the plant and aquatic invertebrate communities become simplified and dominated by pollution-tolerant species. In extreme cases, the wetland may fill in prematurely.

Also, some species are sensitive to human disturbance. If human activity increases in and adjacent to the marsh, some bird species may abandon the area. The species most sensitive to human disturbance, in approximate decreasing order, are Sandhill Crane, Red-necked Grebe, Least Bittern, American Bittern, American Coot, Common Moorhen, and Little Gull.

Mitigation

If development is to occur in wetlands it may not be possible to mitigate its effects on the function of the remaining wetland as a nesting area. Development must be planned to ensure that marsh area is not greatly reduced, particularly to the point where the marsh is incapable of supporting the most area-sensitive species present.

Development within a wetland will greatly affect hydrology and therefore plant communities within the wetland. Development will reduce the storage area of the wetland. If the same watershed is maintained, water levels are likely to increase, thereby reducing the extent of vegetation within the marsh. A water balance should be conducted for any development within a wetland.

Adjacent land development can be benign provided care is taken to ensure that water levels or water quality do not change. An Impact Assessment, however, should consider what setbacks are necessary to reduce the potential for disturbance by humans and pets during the breeding season. Hydrological studies will be required to predict changes in water levels and the duration, magnitude, and frequency of water-level fluctuations. If the wetland receives groundwater inputs, it should be demonstrated that development will not alter the amount of groundwater reaching the wetland. Appropriate stormwater management will be required to ensure that an excess of sediments or nutrients does not reach the wetland. For large-scale developments, a water and nutrient balance may be required to demonstrate that there will be no impact on wetland functions.

For certain species, it may be necessary to control human activities. For the most sensitive species, Sandhill Crane, large-scale or even individual houses within a kilometre of the nesting area may not be compatible with retaining habitat for this species. For some of the more aquatic species that are sensitive to disturbance, it may be necessary to limit use of the wetland by boaters and canoeists during the nesting season.

Development should be designed so as not to encourage heavy human usage of the wetland. Large lots with retention of all shoreline habitat would be preferable. Potential impacts of docks and common roads to the wetland should be determined in an Impact Assessment.

In some cases, habitat may be protected under the provincial wetland policy.


Index #36 - Wetlands/Colonially-Nesting Birds/Seasonal Concentration Area/Nesting Habitat
Index # 36

Habitat Type:	Wetlands

Species Group: 	Colonially-Nesting Birds: Red-necked Grebe, Eared Grebe, Double-crested Cormorant, Least Bittern [VULNERABLE], Great Blue Heron, Great Egret, Snowy Egret, Cattle Egret, Green Heron, Black-crowned Night-Heron, Snow Goose, Ross's Goose, Wilson's Phalarope, Little Gull, Forster's Tern, Black Tern [VULNERABLE], Sedge Wren, Marsh Wren, Lincoln's Sparrow, Yellow-headed Blackbird, Brewer's Blackbird

Significant Wildlife Habitat Category:	Seasonal Concentration Area

Functional Habitat: 	Nesting Habitat

Habitat Function and Composition

This is a diverse group of species that nests in a variety of wetland habitats. Some of the species  nest colonially almost all the time, some tend to be what is termed semi-colonial, while others may nest either in colonies or singly. True colonial species are those that tend to nest together within a small portion of the available habitat, while large areas of suitable habitat may be unused. Many of the true colonial species defend only a very small area around the nest, often only as far as they can reach while sitting on the nest. Others do defend territories, but still nest together even when there are larger areas of unoccupied suitable habitat. Some species, such as  the Red-winged Blackbird are mistakenly thought to be colonial just because they have relatively small territory sizes and are very abundant within the available habitat. Nesting colonially can have several advantages: adults of one pair can alert the entire colony to a potential predator or competitor, the probability of any individual nest or bird being preyed upon is diminished, and colonies can serve as information sources for species that depend on patchy food resources. The latter is particularly true for species that depend on fish for food. The location of good fishing areas may change frequently, and birds may follow successful foragers to new feeding areas. Nesting colonially does have significant risks; entire local populations can be decimated by development, human disturbance, or habitat changes.

For this index, only species that nest colonially in marshes, bogs, fens, and thicket (shrub) swamps have been included. Species that nest colonially in treed swamps have been included in the index on colonially-nesting birds in the woodland/forest habitat category. There is some overlap in the habitat use of some species. For instance, some of the herons may nest either in marshes or forests. In these instances, they have been included in both guilds. Also, some species nest in dead trees in lakes or marshes. These species have been included in this index as well as any other habitat that they may nest in.

Information on habitat requirements of some of the species in this guild are not provided. Some nest only in the Hudson Bay Lowland where they will not be subjected to development pressure. These include the Snow Goose and Ross's Goose. Others are very rare or sporadic in occurrence in the province, so that they do not nest colonially. These include Eared Grebe, Snowy Egret, and Cattle Egret. The Eared Grebe first nested in the province in 1996 at the Emo sewage lagoons in northwestern Ontario. It has the potential to increase and nest colonially, and numbers of nesting pairs have already increased.

The following table summarizes the general characteristics of the nesting habitat of species in this guild when they are nesting within wetlands other than treed swamps.

Species	Habitat Characteristics
Red-necked Grebe	Nests on large, open expanses of marshes or water bodies with a medium density of emergents such as bulrushes, cattails, horsetails, or reed grass; prefers to nest in water 25 to 150 cm deep at a distance of 1 to 18 m from shore; the nest is usually a floating mound of aquatic vegetation; a minimum of 2 ha is required to support a pair, with most birds having a territory size of about 4 ha; generally associated with very large water bodies and marshes in Ontario
Double-crested Cormorant	Occasionally nests in dead, flooded trees in lakes or large marshes; as many as 20 nests may be present in a single tree; nests may be 0.2 to 10 m above water; may nest with other species such as Great Blue Heron and Black-crowned Night-Heron
Least Bittern	Prefers to nest in dense stands of cattails, but also nests in bulrushes, reed grass, horsetails, sedges, grasses, and shrubs; the nest is in emergents in shallow water as deep as 1 m; long-term populations appear to be associated with marshes 100 ha or larger, but it occasionally nests in wetlands as small as 1 ha
Great Blue Heron	Nests in dead trees in large marshes and lakes; nests near the top of trees and is dominant over other smaller species that may nest in the same colony; most nests are 11 to 15 m from ground; readily adapts to using artificial nesting structures; may nest with Double-crested Cormorant, Great Egret, Cattle Egret, Green Heron, Black-crowned Night-Heron, and Osprey; as many as 18 nests have been found in a single tree
Great Egret	Nests in flooded timber and shrubs adjacent to wetlands; may also nest in bulrushes and on the ground, although this has not yet been documented in Ontario; most nests in trees are 4.5 to 9 m from the ground; may nest with Great Blue Herons, Cattle Egret, Green Heron, and Black-crowned Night-Heron
Green Heron	Occasionally nests in flooded timber but more often in shrubs adjacent to or in wetlands; most nests are over water or very close to it; nest heights are usually 3 to 6 m, but may range from 0.2 to 15 m; if larger herons are present in the same colony, it is forced to nest lower
Black-crowned Night-Heron	Nests near water including flooded trees and shrub thickets over and adjacent to water; usually nests in deciduous species, occasionally conifers; rarely nests in emergent vegetation in marshes; most nests are 2 to 4 m above water, but they may be as low as 0.3 m
Wilson's Phalarope	Nests among grasses and sedges at the margins of wetlands or on islands; prefers grasses about 30 cm tall and avoids vegetation taller than 60 cm; the nest is usually near water (<15 m) in a dry location, but one Ontario nest was 45 m away from water; forages in shallow water or on mudflats in wetlands; more frequent in small wetlands than large ones; also nests at sewage lagoons
Little Gull	Nests in marshes associated with large water bodies such as the Great Lakes, occasionally on small ponds; nests are floating or semi-floating mats of aquatic vegetation, or they may be on muskrat houses; usually nests are in open water, occasionally among sedges or cattails; usually nests in water 20 to 70 cm deep
Forster's Tern	Nests in deep-water, large marshes; prefers areas dominated by cattails or bulrushes; nests away from shore, with emergents around islands 0.1 to 1 ha in area being preferred; optimum distance from mainland where water is >50 cm deep is 1 to 3 km; seldom uses marshes smaller than 300 ha; nests are floating masses of aquatic vegetation or are on muskrat houses
Black Tern	Nests in marshes dominated by cattails, but also bulrush, rush, sedge, and bur-reed marshes; prefers a 50:50 ratio of emergents to open water, but also nests in small openings within extensive emergents; rarely nests where water depths are <0.5 m; prefers water depths of about 1 m near the nest; the nest is a floating or anchored mass of aquatic vegetation; it is area-sensitive, rarely occurring in marshes smaller than 20 ha
Sedge Wren	Nests mostly in sedge fens, occasionally in bogs, rarely in cattail marshes, also in old field and hayfields; nests are on the ground or as far as 0.9 m from the ground; most frequently, nests are in clumps of sedges, but they may be at the base of a shrub; usually not associated with standing water, but usually in imperfectly or poorly drained areas
Marsh Wren	Nests mostly in cattail marshes, occasionally in bulrushes, horsetails, bur-reeds, and emergent grasses; nests are usually over water, but occasionally just over damp ground; nests are elevated 0.2 to 1.5 m above water, usually in cattails
Lincoln's Sparrow	Nests mostly in bogs or fens among mosses, grasses, sedges, and ericaceous shrubs, occasionally in willow and alder thicket swamps; nests are usually on the ground, occasionally in forbs or small shrubs at elevations as high as 0.5 m
Yellow-headed Blackbird	Nests in deep-water marshes, mostly among dense cattails but also in bulrushes; nests are attached to emergents; nests in small to large marshes
Brewer's Blackbird	Nests in open bogs with scattered tree or shrub growth; also nests along roads and railway rights-of-way, in clearcuts, in fields and pastures; nests in both dry and wet habitats; most nests are on the ground in or under grasses and forbs, but are occasionally 0.2 to 2.7 m from the ground in a tree
Potential Development Effects

Draining, dredging, excavating, or filling portions of wetlands to establish development will have negative impacts on the function of the wetland as a nesting area for colonially-nesting birds. This may result in direct habitat loss for these species. This may be critical to species that are area dependent. The altered wetland may appear to have suitable habitat, but may be too small to support area-sensitive species. In addition, the smaller wetland basin that will remain is likely to be subject to higher water levels due to reduced storage. The deeper water is likely to reduce the extent of aquatic submergent and emergent vegetation, which is critical to many of these species. Higher water levels are also likely to kill any trees or shrubs that are currently in shallow water or at the water's edge.

Changes to water levels may result from development in adjacent lands. Because marsh birds have specific nest site vegetation density requirements they will abandon sites when vegetation cover becomes too sparse or dense. Changes in the ratio of emergent cover to open water may also affect habitat quality for many species. If significant areas of marshland vegetation are affected, then alternate nesting sites within the marsh may not exist. The marsh may cease to function as colonially-nesting bird habitat.

Water levels may decline if development inhibits groundwater recharge, or if surface water is diverted away from the wetland. Declining water levels are likely to increase the amount of vegetation in the wetland. Lower water levels may make the habitat unsuitable for species that require deeper water, such as Black Terns, Little Gulls, Least Bitterns, Forster’s Terns, and Red-necked Grebes. If water levels decline more than usual during the nesting season, nests that were initiated in shallow water may be more vulnerable to predation.

Water levels may increase if a significant portion of the wetland's watershed is hardened resulting in a higher percentage of precipitation being directed to the wetland. Diversion of water by development may also increase the watershed area. Higher water levels will result in less aquatic vegetation and more open water. This may make the habitat unsuitable for certain species, particularly those that prefer extensive stands of emergents or prefer shallow water. If water levels increase during the nesting season, nests built near the water's surface may be flooded.

Development may also change the frequency, duration, and magnitude of water-level fluctuations. This may have direct impacts on nesting success through flooding of nests or desiccation of critical nesting habitat. Unnatural water-level fluctuations may also affect distribution of aquatic plants and favour invasion by species such as reed grass and purple loosestrife. These plant species do not provide suitable habitat for the species in this guild.

Water quality in the wetland may be altered as a result of runoff from development or due to construction activities. Increases in turbidity as a result of higher sediment and nutrient loadings may reduce the depth that sunlight penetrates into the water column. This reduces the area of the wetland that is capable of supporting aquatic submergents. As water turbidity increases, the plant community becomes less diverse, and is dominated by aggressive, pollution-tolerant species. Invertebrate and fish populations also become less diverse.

Development on adjacent lands may have major effects on colonially-nesting birds owing to disturbance effects. Tree-nesting species appear to be sensitive to pedestrians and often fly from the nest when people are a considerable distance away. Young of tree-nesting species may be lost if they panic due to an intruder and jump from the nest. Where the wetland is a large water body, birds may be disturbed by canoeists or boaters. Wakes from motor boats may result in flooding of nests that are placed on or near the water's surface. Development often results in increased human and pet activity in the wetland.

Mitigation

If development is to occur in wetlands it may not be possible to mitigate its effects on the function of the remaining wetland as a nesting area for colonial nesters. Development must be planned to ensure that wetland area is not reduced. A reduction in wetland size may result in the wetland being incapable of supporting the most area-sensitive species present.

Development within a wetland will greatly affect hydrology and therefore plant communities within the wetland. Development will reduce the storage area of the wetland. If the same watershed is maintained, water levels are likely to increase, thereby reducing the extent of vegetation within the marsh. A water balance should be conducted for any development within a wetland.

Adjacent land development can be benign provided care is taken to ensure that water levels or water quality do not change. Hydrological studies will be required to predict changes in water levels and the duration, magnitude, and frequency of water-level fluctuations. If the wetland receives groundwater inputs, it should be demonstrated that development will not alter the amount of groundwater reaching the wetland. Less water may reduce the size of the wetland. Appropriate stormwater management will be required to ensure that an excess of sediments or nutrients does not reach the wetland. For large-scale developments, a water and nutrient balance may be required to demonstrate that there will be no impact on wetland functions.

For certain species, it may be necessary to control human activities. For the most sensitive species, such as herons, large-scale development or even individual houses near the nesting area may not be compatible with retaining habitat for these species. For some of the more aquatic species that are sensitive to disturbance, it may be necessary to limit use of the wetland by boaters and canoeists during the nesting season. It has been demonstrated that wetland bird species are more sensitive to disturbance by slow-moving watercraft such as canoes than faster-moving power boats.

Development should be designed so that it does not encourage increased human usage of the wetland. Natural shoreline vegetation should be left intact, and roads should not go directly to the wetland.

For some colonial nesters, it may be necessary to leave or create a visual barrier. For example, some of the herons, such as Great Egret and Great Blue Heron, are sensitive to human presence during the breeding season.

Information is available on set-back distances for some colonially-nesting species. Within these setbacks, there should be no human activity such as walking or canoeing. Generally, there should be no human incursion within 100 m of nesting herons and 200 m of nesting terns.


Index #37 - Wetlands/Waterfowl/Seasonal Concentration Areas/Staging Areas
Index # 37

Habitat Type:	Wetlands

Species Group: 	Waterfowl: ducks, geese, swans

Significant Wildlife Habitat Category:	Seasonal Concentration Areas

Functional Habitat:	 	Staging Areas

Habitat Function and Composition

Waterfowl often stop in traditional areas during spring and autumn migration to rest, feed and/or wait out bad flying weather. Large numbers of migrating waterfowl may concentrate in traditionally used areas. The length of time that individual birds stay in staging areas varies. Large numbers may leave together if ideal weather conditions arise. Some species of waterfowl using staging areas may forage in nearby agricultural crops. Sometimes the most important staging areas are the only large marshes with open water in the surrounding area. Therefore, all of the birds tend to gravitate to that site.

Waterfowl staging habitat requirements are somewhat different in spring and autumn, as described for some species below. This may relate to where the birds nest and how close they are to the nesting or wintering areas. Many birds arrive on the lower Great Lakes unpaired in the spring, while others pair during winter. Pairing for the first group of species may occur on the Great Lakes and major southern rivers, and is completed by the time the nesting areas are reached. Some of the more arctic species may stage in large numbers in the south waiting for the breeding grounds to thaw. In autumn, migration is often more leisurely, with birds often remaining until freeze-up.

Staging areas are an important component of migration traditions. The network of staging areas which occurs in major North American waterfowl flyways ensures safe conveyance of birds between winter and summer range. Large coastal or lakeshore wetlands may also serve as navigation aids to migrating waterfowl. Staging areas are often situated at a point in the migration where the birds need to replenish energy reserves and rest before continuing.

Waterfowl use a variety of wetlands as staging areas. Larger wetlands seem to be preferred and those associated with shorelines attract the largest concentrations. Marshes which provide a good interspersion of open water and emergent plant cover are high quality sites because they provide an optimum mix of food and cover. Some of the autumn staging areas are also used as night-time roosts. Several hundred waterfowl may use a larger pond or wetland as an over-night roost, dispersing to smaller water bodies during the day to feed. Night-time roosts are often thick willow thicket swamps or wetlands with a mix of marsh and swamp. These sites are important in providing cover and protection from predators, but they may be deficient in food supplies.

The various waterfowl species have slightly different habitat requirements while they are at a migration stopover. The following table summarizes these habitat characteristics:

Species	Habitat Characteristics
Tundra Swan	In spring, congregates along the shorelines of the lower Great Lakes; also occurs in smaller numbers on inland lakes and ponds, as well as spring-melt areas in agricultural fields; eats mostly aquatic submergents taken from water as deep as 0.5 m, also eats roots and stems of emergents and agricultural crops such as corn, grain, and soybeans
Snow Goose	Usually flies directly to the breeding areas in spring with no concentrations in staging areas; in autumn, stages in large numbers on islands and tidal flats in southern James Bay; some stopover in the south, usually in large marshes or lakes; often in the company of Canada Geese; eats mostly shoots and tubers of aquatic plants during migration, but some have adapted to feeding on agricultural crops
Canada Goose	Limited staging occurs in spring, mostly at Lake St. Clair, Long Point, and the Detroit River; in autumn, primary staging areas are lakes, ponds, marshes, and agricultural fields; feeds mostly on waste grains and grasses
Green-winged Teal	Uses ponds, marshes, lakes, and watercourses during migration; eats mostly aquatic vegetation in shallow water or on mudflats; occasionally feeds in agricultural fields in autumn
American Black Duck	Prefers extensive marshes with nearby agricultural fields; smaller numbers may occur on beaver ponds and watercourses; eats mostly aquatic invertebrates and vegetation, but also occasionally feeds in agricultural fields
Mallard	Prefers ponds and marshes with sparse or moderate vegetative cover; important habitat features are abundance and variety of aquatic plants, proximity of grain fields, off-shore loafing areas, and the presence of wide, shallow, littoral areas; extensive marshes adjacent to grain and corn fields are optimum habitat; in spring also uses meltwater ponds in agricultural fields; in spring, eats mostly invertebrates and aquatic vegetation; in autumn, eats mostly corn and grain; extensive field feeding seldom occurs near marshes smaller than 20 ha, and it prefers fields immediately adjacent to wetlands
Northern Pintail	In spring, uses flooded fields and low-lying areas along watercourses; in autumn, it is associated with large marshes and fields; often field feeds with Mallards
Blue-winged Teal	In spring, occurs on small ponds, marshes, ditches, and slow-flowing streams; prefers areas with emergent vegetation; seldom occurs in large numbers in spring; in autumn, large flocks are associated with large marshes, but smaller numbers may occur on ponds and streams; eats mostly invertebrates and plant seeds; does not normally feed on crops
Northern Shoveler	Seldom occurs in flocks in spring, may be more common in autumn; prefers shallow ponds and marshes where there is vegetation floating on the water; eats wetland plants and weeds that have been flooded
Gadwall	Prefers large, deep-water marshes with an abundance of aquatic submergents such as pondweeds and water-milfoil; eats mostly aquatic invertebrates in spring and leaves and stems of aquatic submergents in autumn; occasionally field feeds
American Wigeon	Prefers large (>20 ha) marshes and open water bodies; eats mostly the foliage of submergent aquatic macrophytes; occasionally feeds in grain fields
Canvasback	Occurs primarily in large marshes on the lower Great Lakes (Long Point, Turkey Point, Walpole Island, Lake St. Clair, Detroit River, Rondeau Bay); occasionally appears in smaller numbers on large, inland marshes and lakes; prefers deep-water marshes with an abundance of the submergent plants that it feeds on
Redhead	Associated mostly with large marshes on the lower Great Lakes (Lake St. Clair, Walpole Island, Detroit River, Long Point, Turkey Point, Presqu'ile Bay, Bay of Quinte); also occurs on large inland lakes and marshes; prefers open water with an abundance of submergents, particularly pondweeds; feeds on submergents
Ring-necked Duck	Largest concentrations are in marshes on the lower Great Lakes, but it is also common on inland lakes, ponds, marshes, and watercourses; eats mostly pondweeds, bulrush tubers, and bur-reeds, plus snails, clams, and aquatic insects
Greater Scaup	Most staging is on the Great Lakes, but it also occurs on large inland lakes, marshes, and rivers; rafts in open water bodies, but the presence of suitable emergents or aquatic invertebrates for food is essential; may also feed on zebra mussels
Lesser Scaup	Habitat and diet are similar to the Greater Scaup; both species often stage together
Common Goldeneye	Occurs on large rivers, inland lakes and marshes, and the Great Lakes; prefers areas with aquatic vegetation, but also uses areas devoid of vegetation; eats mostly aquatic insects, crustaceans, and molluscs, but also aquatic plants
Bufflehead	Flocks prefer large rivers, marshes, and lakes, but individuals or pairs may use very small ponds; prefers open water with a sand substrate and limited aquatic vegetation; eats mostly aquatic insects
Hooded Merganser	Seldom occurs in large numbers; prefers small ponds, marshes, lakes, and medium-sized watercourses; eats mostly aquatic insects, crayfish, and small fish
Ruddy Duck	Restricted to large marshes and lakes; prefers deep water adjacent to emergents; feeds on clams, snails, aquatic insects, and aquatic vegetation
Potential Development Effects

Draining, dredging, excavating, or filling portions of wetlands to establish development will have negative impacts on the function of the wetland as a waterfowl staging area. This may result in direct habitat loss for these species. In addition, the smaller wetland basin that will remain is likely to be subject to higher water levels due to reduced storage. The deeper water is likely to reduce the extent of aquatic submergent and emergent vegetation, which is critical to many of these species. Deeper water may also kill shrubs and trees living on hummocks in the water or along the shoreline. Some of the waterfowl species in this guild require large wetlands so that they are safe from predators and disturbance. If the wetland area is decreased, habitat may no longer be suitable for area-sensitive species.

Changes to water levels may result from adjacent development. Because many migrating waterfowl species have specific vegetation density or species requirements they will abandon sites when vegetation cover becomes too sparse or dense, or if dominant species change. Changes in the ratio of emergent cover to open water may also affect habitat quality for many species. If significant areas of marshland vegetation are affected, then the marsh may cease to function as waterfowl staging habitat.

Water levels may decline if development inhibits groundwater recharge, or if surface water is diverted away from the wetland. Declining water levels are likely to increase the amount of vegetation in the wetland and change the vegetation composition. Lower water levels may make the habitat unsuitable for species that require deeper water and more submergents than emergents. This can be a serious problem on many inland ponds and marshes. Too little water is probably more detrimental to waterfowl staging than too much water.

Water levels may increase if a significant portion of the wetland's watershed is hardened resulting in a higher percentage of precipitation being directed to the wetland. Diversion of water by development may also increase the watershed area. Higher water levels will result in less aquatic vegetation and more open water. This may make the habitat unsuitable for certain species, particularly those that prefer extensive stands of emergents or prefer shallow water. Deeper water may enhance conditions for species that prefer submergents, at the expense of those that require emergents.

Development may also change the frequency, duration, and magnitude of water-level fluctuations. Unnatural water-level fluctuations may affect distribution and diversity of aquatic plants and favour invasion by species such as reed grass and purple loosestrife.

Water quality in the wetland may be altered as a result of runoff from the development or due to construction activities. Increases in turbidity as a result of higher sediment and nutrient loadings may reduce the depth that sunlight penetrates into the water column. This reduces the area of the wetland that is capable of supporting aquatic submergents. As water turbidity increases, the plant community becomes less diverse, and is dominated by aggressive, pollution-tolerant species. Invertebrate and fish populations also become less diverse. These factors reduce habitat quality for staging waterfowl.

Development on adjacent lands may have major effects on staging waterfowl owing to disturbance effects. Many of the species are sensitive to human activities; this is why some of them are restricted primarily to larger water bodies and wetlands. Where the wetland is a large water body, birds may be disturbed by boats. This has been demonstrated to be a problem for staging waterfowl on the lower Great Lakes. Removal of adjacent land cover may result in visual disturbance as many waterfowl species prefer seclusion.

Development of cropland adjacent to wetlands may also reduce the function of the marsh for supporting staging waterfowl. Certain of the species tend to rely on corn and other grains during autumn migration. This is usually a concern only with fields that are adjacent to marshes larger than 20 ha. Also, those species that are field feeders are mostly common species that are not at risk; in fact, some of them are extremely abundant in some areas almost to the point of being a nuisance (e.g. Canada Goose).

Mitigation

If development is to occur in wetlands it may not be possible to mitigate its effects on the function of the remaining wetland as a significant waterfowl staging area. Development must be planned to ensure that marsh area is not greatly reduced, particularly to the point where the marsh is incapable of supporting the most sensitive species present.

Development within a wetland can greatly affect hydrology and therefore plant communities within the wetland. Development will reduce the storage area of the wetland. If the same watershed is maintained, water levels are likely to increase, thereby reducing the extent of vegetation within the marsh. A water balance should be conducted for any development proposed within a wetland.

Adjacent land development can be benign provided care is taken to ensure that water levels or water quality do not change and that it is designed in such a manner that subsequent human activities are not too disturbing. Hydrological studies will be required to predict changes in water levels and the duration, magnitude, and frequency of water-level fluctuations. If the wetland receives groundwater inputs, it should be demonstrated that development will not alter the amount of groundwater reaching the wetland. Appropriate stormwater management will be required to ensure that an excess of sediments or nutrients does not reach the wetland. For large-scale developments, a water and nutrient balance may be required to demonstrate that there will be no impact on wetland functions.

For certain species, it may be necessary to control human activities. For the most sensitive species, large-scale development near the staging area may not be compatible. For some of the species that are sensitive to disturbance, it may be necessary to limit use of the wetland by boaters and canoeists during the migration season. Development should be designed so as not to promote or encourage increased use of the wetland. For example, no roads should be built right to the wetland, and all natural vegetation should be left between the development and the wetland.

In some cases, it may be possible to expand the wetland. This type of mitigation should not be planned as a trade-off for destroying some of the wetland. Proponents wishing to enhance wetland functions or size should refer to the Temperate Wetland Restoration Guidelines.

In some instances, it may be necessary to maintain active agricultural land adjacent to a staging area to provide food for staging waterfowl. This should be necessary only when significant numbers of birds rely on this resource. In some instances, it may not be logical to provide agricultural crops for migrating waterfowl, particularly if the species are very common. In many cases, the dominant species using this resource is the Giant Canada Goose, which is basically a non-migratory species in the province and its population continues to grow.


Index #38 - Woodland/Forest/Wetland/Swamp/Colonial-Nesting Birds/Seasonal Concentration Area/Nesting Habitat
Index # 38

Habitat Type:	Woodland/Forest; Wetland/Swamp

Species Group: 	Colonial-Nesting Birds: Great Blue Heron, Great Egret, Green Heron, Black-crowned Night-Heron

Significant Wildlife Habitat Category:	Seasonal Concentration Area

Functional Habitat: 	Nesting Habitat

Habitat Function and Composition

These herons nest in a variety of wetland and forested habitats. Some of the species nest in colonies almost all the time, while others may nest either in colonies or singly. True colonial species are those that tend to nest together within a small portion of the available habitat, while large areas of suitable habitat may be unused. Many of the true colonial species defend only a very small area around the nest, often only as far as they can reach while sitting on the nest. Others do defend territories, but still nest together even when there are larger areas of unoccupied suitable habitat. Nesting in colonies can have several advantages: adults of one pair can alert the entire colony to a potential predator; or competitor, the probability of any individual nest or bird being preyed upon is diminished; and colonies can serve as information sources for species that depend on patchy food resources. Nesting  in colonies does have significant risks; entire local populations can be decimated by development, human disturbance, or habitat changes.

For this index, only species that nest in colonies in woodland/forest habitat have been included. The four species in this guild may also nest in wetland habitats, and they are included in Index 36 which deals with colonial-nesting wetland bird species. Some of these species nest in dead trees in lakes or marshes. They have been included in this index as well as any other habitat that they may nest in.

The following table summarizes the general characteristics of the nesting habitat of species in this guild when they are nesting within forested habitat:

Species	Habitat Characteristics
Great Blue Heron	Nests in dead trees in large marshes and lakes and in live soft maple swamps;  most nests are 11 to 15 m from ground; as many as 18 nests have been found in a single tree; in the south, it tends to nest in large deciduous swamps; these colonies may be used for several years, although the birds’ excrement may eventually kill the trees; nesting colonies in the south tend to be much larger than in the north; on the Shield, it frequently nests in much smaller colonies in standing timber in beaver ponds; these heronries are often used for only a few years
Great Egret	Nests in flooded timber and shrubs adjacent to wetlands; most nests in trees are 4.5 to 9 m from the ground; may nest with Great Blue Herons, Cattle Egret, Green Heron, and Black-crowned Night-Heron
Green Heron	Occasionally nests in flooded timber but more often in shrubs adjacent to or in wetlands; most nests are over water or very close to it; nest heights are usually 3 to 6 m, but may range from 0.2 to 15 m; if larger herons are present in the same colony, it is forced to nest lower; it also nests in upland coniferous plantations, usually in pine trees; in plantations, nests tend to be near the tops of the trees, 6 to 8 m from the ground; heronries in plantations may be as far as 2.5 m from water; heronries in plantations tend have very large wetlands or other quality feeding areas nearby
Black-crowned Night-Heron	Nests near water including flooded trees and shrub thickets over and adjacent to water; usually nests in deciduous species, occasionally conifers; most nests are 2 to 4 m above water, but they may be as low as 0.3 m
Potential Development Effects

In many cases, the forested habitat for these species is wetland. Draining, dredging, excavating, or filling portions of wetlands to establish development will have negative impacts on the function of the wetland as a nesting area for colonially-nesting birds. This may result in direct habitat loss for these species. In addition, the smaller wetland basin that will remain is likely to be subject to higher water levels due to reduced storage. Higher water levels are likely to kill any trees or shrubs that are currently in shallow water or at the water's edge, and these may be used as nesting habitat for some of these species.

Forest clearing may have direct impacts on these species through loss of nesting habitat, or indirect effects such as reducing the buffer area between the nesting colony and human activity.

Water levels may decline if development inhibits groundwater recharge, or if surface water is diverted away from the wetland. The water table may be lowered, and this could promote drying of the forest cover and conversion to upland habitat, which is seldom used other than by the Green Heron. Drying may also promote windthrow in swamps, resulting in the loss of the larger trees that are preferred for nesting. Where colonies are situated in flooded timber, greatly reduced water levels make the nests susceptible to predators such as raccoons, and heronries are often abandoned if water levels decline significantly.

Development on adjacent lands may have major effects on colonially-nesting birds owing to disturbance effects. Tree-nesting species appear to be sensitive to pedestrians and often fly from the nest when people are a considerable distance away. Young of tree-nesting species may be lost if they panic due to an intruder and jump from the nest. Development often results in increased human and pet activity in the wetland.

Mitigation

If development is to occur in woodlands it may not be possible to mitigate its effects on the function of the remaining woodland as a nesting area for colonial nesters. Development must be planned to ensure that forest area is not reduced. A reduction in forest size may result in the woodland being incapable of supporting species sensitive to human disturbance.

Development within a woodland will greatly affect hydrology and therefore tree species composition. A water balance should be conducted for any development within or adjacent to a lowland forest supporting a heron colony.

Adjacent land development can be benign provided care is taken to ensure that water or water- table levels do not change. Hydrological or hydrogeological studies may be required to predict changes in water levels and the duration, magnitude, and frequency of water-level fluctuations. If the site receives groundwater inputs, it should be demonstrated that development will not alter the amount of groundwater reaching the woodland

For these species, large-scale development or even individual houses near the nesting area may not be compatible with retaining habitat. Development should be designed so that it does not encourage increased human usage of the woodland. It may be necessary to leave or create a visual barrier. Herons are sensitive to human presence during the breeding season. Information is available on set-back distances for some colonially-nesting species. Within these setbacks, there should be no human activity such as walking or canoeing. Generally, there should be no human incursion within 100 m of nesting herons.


Index #39 - Woodland/Forest/Kirtland's Warbler/Habitat of Species of Conservation Concern/Nesting Habitat
Index # 39

Habitat Type: 	Woodland/Forest

Species Group:  	Kirtland’s Warbler [ENDANGERED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Nesting Habitat

Habitat Function and Composition

Although breeding by Kirtland’s warblers appears to be restricted to central Michigan, there have been records of its occurrence in Ontario. There is one documented case of its nesting near Barrie in 1945. This species is highly specialized in its selection of nesting habitat. It nests only in relatively pure stands of young jack pine.

The Kirtland's Warbler selects essentially pure stands of young jack pine more than about 30 ha in area growing on well-drained sandy soil or shallow soils covering bedrock. Although it has nested in stands as small as 20 ha, homogeneous jack pine tracts larger than 200 ha appear to be required for long-term population viability. Trees 1.5 to 2 m in height are colonized first, and stands will continue to be occupied until trees are about 5 m tall and the lower limbs start to die. Jack pines approximately 6 to 15 years of age fulfil the nesting habitat requirements of the Kirtland's Warbler. Any jack pine stands matching this description in southern Ontario could function as Kirtland’s Warbler habitat.

Because of its requirement for very young jack pine stands, its distribution is highly dependent on natural stochastic events such as forest fires. In the absence of natural or managed disturbances, habitat quickly becomes unsuitable for this species.

This is one of the rarest bird species in North America because of its very specialized habitat requirements. It has teetered at the brink of extinction for centuries. Therefore, any nesting habitat within the province would be highly significant.

Potential Development Effects

Development which affects pure stands of jack pine, particularly young stands, will impact Kirtland’s Warbler habitat.

Tree cutting and lot clearing present the greatest threats to Kirtland’s Warbler habitat. If jack pine stands are reduced in size below about 30 ha, then the function of the habitat for breeding will be eliminated. In fact, viable populations may not exist if the size of the habitat declines below 200 ha.

Forest fragmentation is also a serious threat. The Kirtland's Warbler is highly vulnerable to cowbird parasitism. In areas that are not managed for cowbird control, nest parasitism rates average 75%. As blocks of suitable habitat decrease in size or are fragmented, the incidence of parasitism is likely to increase resulting in lowered reproductive success.

Development on adjacent land is not expected to directly affect the function of jack pine stands as breeding habitat for Kirtland’s Warblers. There are two potential indirect effects that may be highly significant to continued viability of Kirtland's Warblers. These include fire suppression and human disturbance.

The Kirtland's Warbler requires fire or other large-scale disturbances to provide young jack pine stands. With the presence of development adjacent to its habitat, there will be public pressure reduce the risk of forest fire and to extinguish any that do occur as quickly as possible. This will limit the viability of the area for Kirtland's Warbler breeding habitat.

Because the Kirtland's Warbler is an extremely rare species, it is much sought after by birders. The presence of development near its breeding habitat is likely to increase the number of people that know of its whereabouts and want to see it. Excessive disturbance could affect breeding success.

Mitigation

Mitigating the effects of development on Kirtland’s Warbler habitat involves the protection of pure stands of young jack pine. The Kirtland's Warbler is protected under the Ontario Endangered Species Act and Policy 2.3 of the Provincial Policy Statement states that no development shall occur in the significant portions of the habitat of threatened and endangered species. This includes its breeding areas. Because it is highly area sensitive and extremely vulnerable to cowbird parasitism, development should not be permitted in any jack pine stand that supports breeding Kirtland's Warblers.

If development is proposed adjacent to Kirtland's Warbler nesting habitat, programs must be implemented to restrict human usage of the area. Casual visitation by small numbers of local residents is unlikely to have significant impacts. However, use of the area by high numbers of birders should be avoided. Development should be set back a minimum of 30 m from jack pine stands providing habitat for nesting Kirtland’s Warblers unless an Impact Assessment can demonstrate that a lesser set back will protect nesting Kirtland’s Warblers.

Prior to development occurring adjacent to Kirtland's Warbler habitat, a management plan should be prepared and approved by the Ministry of Natural Resources and the Canadian Wildlife Service. This may include controlled burns, clearcuts, planting, and cowbird management.


Index #40 - Woodland/Forest/Amphibians/Seasonal Concentration Area/Breeding Ponds
Index # 40

Habitat Type: 	Woodland/Forest

Species Group: 	Amphibians: red-spotted newt, Jefferson salamander, blue-spotted salamander, spotted salamander, smallmouth salamander [VULNERABLE], American toad, gray treefrog, spring peeper, chorus frog, wood frog, leopard frog, pickerel frog, green frog

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat: 	Breeding Ponds

Habitat Function and Composition

Most amphibians require a source of water to reproduce. During spring, these species concentrate in woodland ponds to mate and lay eggs. Eggs are laid in water where they hatch as larvae. The larvae live in the water for varying lengths of time depending on the species, and eventually emerge as adults. The red-spotted newt is an exception in that the larvae live on land for several years, returning to woodland ponds to live as adults. Adults of other amphibian species either live in the pond or at its edge, disperse away from the pond once they emerge to live in terrestrial habitats some distance from the pond returning in spring to breed or autumn to hibernate in bottom sediments. Breeding ponds may be along the edge of swamps, in floodplains, in groundwater seeps, or in depressions in upland forests.

For a woodland pond to function as a breeding pond it requires the following elements:

1)	Shallow, unpolluted water which may be permanent or temporary. If the water source is temporary it must hold water for a long enough time for larvae to develop into adults before the pond dries up. Permanent ponds with populations of predatory fish are poor quality breeding sites owing to the high mortality rate fish exert on larvae.

2)	Emergent and submergent vegetation may be used for calling sites and structure for egg laying. For some species, woody shrubs along the shoreline are valuable elements. Logs and other shoreline structures are important for calling, resting, and providing escape cover from a variety of predators.

3)	Surrounding woodland habitat of various compositions must provide a closed canopy offering a shaded, moist understory to retain breeding pond function. The forest understory should offer an abundance of downed woody debris to act as cover for amphibians while they are living in terrestrial habitats. It is very important that breeding ponds be close to summer habitat.

Timing of breeding, the length of time required for larvae to transform into adults, and specific habitat requirements differ among species. Many of these parameters are important in determining what breeding species of amphibians a pond can support.

The following table summarizes important habitat requirements and chronology of amphibians that breed in woodland pools. For many of the mole salamanders that breed early in the spring, the presence of some green algae is important. The algae provide oxygen which is essential in the development of the eggs. This may also be an important factor for some other groups of amphibians.

Species	Habitat Characteristics and Life History Chronology
Red-spotted Newt	Breeds in permanent ponds, usually with dense submergent vegetation; breeding ponds are usually within or a short distance from forests; breeds from April to June with adults that were aquatic over winter breeding earlier than those that wintered on land; eggs are attached singly to submergent vegetation and hatch in 1 to 2 weeks; larval period lasts 1 to 2 months; transform into red efts that move out into the forest and also into adjacent open habitats
Jefferson Salamander	Hybridizes with the blue-spotted salamander and the two species and their hybrids cannot safely be distinguished in the field; usually breeds in pools in rich upland forests, less frequently in swamps; may occasionally use ponds a short distance from forest; moves to the breeding ponds in March or early April with the first spring rains; breeds very early,often before ice is completely gone from the pond; uses both temporary and permanent ponds; eggs are laid in masses on sticks or vegetation and hatch in about 30 days; larvae transform in about 95 days, or around early August; adults leave the pond shortly after breeding, young leave as soon as they transform; adults remain in forest habitat and hide under logs or burrow into the soil
Blue-spotted Salamander	Breeds in a wide variety of forest cover including deciduous, mixed, and coniferous upland and lowland stands; also breeds in ponds, marshes, and roadside ditches away from forest; breeding coincides with the first spring rains in March or early April, often before the pond is completely ice free; lays eggs singly or in pairs on leaves or other litter on the bottom of the pond; eggs hatch in 3 to 4 weeks, and larvae begin to transform in mid July, occasionally as early as late June; complete transformation may take until early August; adults leave the pond shortly after breeding, young leave as soon as they transform; adults remain in forest habitat and hide under logs or burrow in the soil, some wander out into open habitat
Spotted Salamander	Prefers well-drained, upland deciduous and mixed forests with or adjacent to permanent or temporary pools; breeds very early in the spring, occasionally before ice is totally gone; eggs are laid in masses on twigs and branches in the pond; hatching period and larval transformation time is highly dependent on water temperature; hatching takes 39 to 54 days, and transformation another 61 to 113 days; overwintering of larvae has been reported from other areas; adults leave the pond shortly after breeding, young leave as soon as they transform; adults remain in forest habitat and hide under logs or burrow into the soil
Smallmouth Salamander	Occurs only on Pelee Island in Ontario; breeds very early in the spring shortly after the first rains; breeds in woodland pools, but also in roadside ditches on the island; eggs are deposited singly or in small clusters on stems and sticks below the surface of the water; hatching takes 25 to 38 days; transformation probably takes place in late June or July; adults leave the breeding area shortly after breeding and young leave as soon as they transform
American Toad	Breeds in temporary and permanent woodland pools, plus a wide variety of other habitats: marshes, ditches, open ponds, manmade ponds and pools in agricultural and urban areas; has the widest breeding niche of Ontario's amphibians; breeds around mid April until early May in the south; lays eggs in two strands which are wrapped around plants, rocks, and twigs; eggs hatch in 3 to 12 days depending on water temperature; tadpoles transform in 50 to 65 days, and young often leave the pond before the end of June; adults may remain in forest habitat or move to open areas such as fields and residential areas
Gray Treefrog	Breeds in a wide variety of habitat including swamps, marshes, farm ponds, flooded farmland, and floodplains; uses temporary and permanent pools; breeding occurs from mid May until early July; eggs are laid as floating packets and hatch within 5 days; tadpoles take 40 to 60 days to transform into adults, with transformation usually occurring in late July or early August; adults are arboreal and may remain in forest habitat or move to shrublands or rural residential areas
Spring Peeper	Breeds mostly in pools in second growth forests or swamps, but also in isolated ponds with margins of emergents or shrubs; prefers ponds where there are trees or shrubs along the shoreline, but also uses areas of herbaceous emergents; egg-laying starts in late March or early April in the south; eggs are laid singly or in small groups on submerged twigs and leaves; egg hatching takes about 15 days, depending on water temperature; transformation takes 90 to 100 days, usually during the last half of June; most adults remain in forest habitat, but some move to more open areas
Chorus Frog	Prefers shallow, temporary pools with abundant vegetation for breeding, but will occasionally use permanent ponds; breeds in woodlands, but also in disturbed habitats such as agricultural areas, shrublands, and meadows; requires areas with emergent or floating aquatic vegetation; breeding begins very early in the spring, often in late March and always by early April in the south; eggs are laid in small masses on submerged twigs; egg hatching takes about 2 weeks; transformation is rapid and may begin by the end of June; adults usually remain in wetland areas
Wood Frog	Prefers ponds in swamps, particularly those with many leaves on the bottom of the pond; may also breed in marshes and ponds a short distance from woodlands; breeding begins in late March in the south and lasts about 3 weeks; eggs are laid in a round mass and are usually attached to a twig or branch underwater; eggs hatch in 17 to 24 days; the average time for tadpole transformation is 67 days, but ranges from 44 to 85 days; adults remain in forest habitat
Leopard Frog	Breeds in a variety of habitats including woodlands, but also dugout ponds and other manmade aquatic habitat, marshes, flooded fields, and floodplains; breeding generally occurs from mid April to early to mid May; eggs are laid in masses and hatch in about 3 weeks; tadpoles transform in 60 to 80 days depending on water temperatures; in the south, young leave the pond in late June or early July; adults disperse into damp meadows
Pickerel Frog	Appears to require cool water where there is groundwater seepage, but not necessarily for breeding; has breeding habitat preferences similar to those of the leopard frog; breeding occurs in late April or early May; eggs are laid in clusters on submerged twigs in shallow water; eggs hatch in 11 to 21 days; transformation takes about 80 days; adults disperse into damp meadows
Green Frog	Not particularly dependent on woodland pools, being more common in other habitat; requires permanent water bodies such as lakes, large marshes, ponds in rural areas, and slow-flowing streams and rivers; egg laying may begin in mid May, but may continue until early August; eggs are laid in a mass over submerged plants; eggs hatch in 3 to 6 days; tadpoles require about a year to transform; therefore, this species must breed in permanent ponds to be successful; adults usually remain in the pond, or may move to other ponds
Potential Development Effects

Development which results in the draining or filling of small woodland ponds will destroy the function of the pond and the surrounding land for amphibians. The loss of the breeding pond will affect the population dynamics of essentially all amphibian populations in the vicinity of the development.

Development on adjacent land can have significant impacts on breeding pond functions if it alters ground or surface water flow. Woodland ponds which dry up before larvae transform as a result of disruptions to hydrological function become unsuitable sites for reproduction. Adjacent development can have a very high impact if it separates breeding habitat from summer or winter habitat.

Development which is likely to result in the release of contaminants (i.e. road salt, sediments, high nutrient concentrations, gasoline and oil, etc.) in surface runoff will affect breeding ponds owing to the sensitivity that amphibians show to aquatic toxicants. Excessive nutrients will promote growth of algae. Although the presence of some algae aids in the oxygenation of pond water, algae blooms result in deoxygenation.

Development may affect amphibian populations and hence the function of breeding ponds and summer range through human disturbance. Lot clearing, frog catching, and predation by pets can have considerable effects on some amphibian populations. These activities may impact breeding ponds even if development occurs on adjacent lands.

Tree cutting in the vicinity of the pond or development in terrestrial habitats used as summer range can affect amphibian habitat by changing the moisture regime of the woodland. The impacts will be on breeding ponds and surrounding woodland used as summer habitat. Dry conditions greatly reduce the quality of woodland habitat for most amphibians. Reducing the amount of shade in the vicinity of the pond can result in premature drying of the pond and excessive growths of algae. The length of time the pond holds water in the spring is critical. Forest fragmentation may reduce habitat for adults of certain species after they leave the breeding pond.

Dredging and clearing of shoreline vegetation and other in-pond structures (logs, stones, etc.) greatly reduces the quality of the pond as a breeding site. The loss of structure increases predation and affects amphibian populations within the pond and surrounding woodland.

Road construction can have considerable impact on amphibian populations. As adults move to and from breeding ponds large numbers are often killed by vehicles. This can be devastating, particularly in the spring. During cool spring nights, frogs may be attracted to the warmer road surface. Juveniles are also at risk as they disperse away from breeding ponds.

Mitigation

Ideally, development should not occur in or directly affect significant amphibian breeding ponds. The effects of development on breeding pond functions can be made less severe by ensuring that local water levels are not negatively affected or contaminated. This will require appropriate stormwater management and ensuring that groundwater recharge and discharge functions will not be altered by development in a manner which will affect the pond.

Steps should be taken to ensure that forest cover remains intact around the pond allowing seasonal movement to and from the pond. There should be no removal of aquatic vegetation or other structures (logs, stones, etc.) from the pond or shoreline in an attempt to “clean it up”. Simplifying the structural complexity of the pond will have huge impacts on its function as a breeding pond.

If development will totally remove the pond there may be opportunity to create alternate breeding ponds in adjacent forest land if it is available and of suitable structure (i.e. relatively large woodlot, preferably connected to others, closed canopy, moist understory, with plenty of downed woody debris). Shallow dug ponds will begin functioning as breeding ponds  relatively quickly provided they can be reached by amphibians dispersing from other areas. Populations of amphibians inhabiting the original breeding pond and surrounding habitat will be severely reduced by development activities. It is not safe to assume that they will simply move to the newly-created site and take up residence there. The amphibian community which is established in the new pond may bear little resemblance to the original one (i.e. different number and kinds of amphibians).

Road systems should be designed so that they do not run parallel to breeding ponds or cut off summer habitat from the breeding pond so that road mortality is minimized.

Breeding ponds will not retain their function if suitable surrounding summer habitat is not maintained. Wetlands and other moist habitats must be preserved. For mole salamanders and other amphibians that spend their adult life in forest habitat, it is essential to maintain adequate forest cover. The forest must not be excessively fragmented so that it is too small to support the species initially inhabiting it. Salamander populations will also be adversely affected if logs and other ground structures are removed from the woodlot. In addition to their requirement for moist areas in the summer, mole salamanders need dry areas within the woodlot to spend the winter. Care is required to ensure that winter habitat is not destroyed by development.

A large area of natural habitat should be maintained near a large development to ensure that all of the life history requirements of amphibians residing in the area are fulfilled. An Impact Assessment should address the amount of natural area that should be maintained or created.

For rural residential development on large lots, areas of forest and ephemeral and permanent ponds should be retained. Where possible, clustering development may leave a higher proportion of natural area.


Index #41 - Woodland/Forest/Forest Interior Birds/Habitat of Species of Conservation Concern/Breeding Habitat
Index # 41

Habitat Type: 	Woodland/Forest

Species Group:  	Forest Interior Birds

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Breeding Habitat

Habitat Function and Composition

Birds vulnerable to forest fragmentation (often referred to as forest-interior or area-sensitive) require large continuous blocks of forest for successful nesting. Forests provide shelter, nesting habitat, and food for these birds. This is a large guild of species, and their habitat requirements are not fully understood. Forest-interior species are those that tend to avoid edges, while area-sensitive species require habitat patches of a certain size before they are inhabited. Distinctions between these two groups are not clear, and vary within individual species depending on the amount of forest cover in the regional landscape. It appears that when species are nesting in forests near the minimum size that they inhabit, that they nest in the interior. As forest size increases, they may nest throughout the forest, even on edges. Some species that require large forested tracts nest only on the edge and avoid the interior, resulting in susceptiblity to forest fragmentation.

The habitat requirements of breeding birds susceptible to habitat fragmentation are extremely variable and complex. For some, the total amount of woodland in the regional landscape is more important than the size of the woodlot that is selected for nesting. Shape and size of woodlots are critical to other species; woodlots with irregular edges and openings within the forest have a lower potential to support species that prefer forest interior. Some species may nest near woodland edges or openings, but still require extensive forest cover. Other important variables may include moisture regime, stand maturity, density of understory, and tree species composition.

There is one group of species that requires extensively forested landscapes and, in Ontario, they occur primarily on the Canadian Shield. Some of these nest far from edge, while others prefer openings and edges within extensive forests. These species are not particularly susceptible to development unless nest sites are affected or the amount of forest cover within the surrounding 10 km2 is significantly reduced. Species in this category include Spruce Grouse, Northern Hawk Owl, Great Gray Owl, Boreal Owl, Common Nighthawk, Three-toed Woodpecker, Black-backed Woodpecker, Gray Jay, Common Raven, Boreal Chickadee, Rusty Blackbird, and Pine Grosbeak. These species are not discussed in more detail in this index. One of these species, the Common Nighthawk, nests in the south, but has abandoned its natural habitat to nest primarily on manmade structures.

Forest fragmentation effects on breeding birds is generally a concern only in off-Shield southern Ontario. Therefore, species which may be susceptible to forest fragmentation but that do not normally breed in the south have been excluded from further consideration. However, these principles can still be applied to development on the shield. These are Olive-sided Flycatcher, Ruby-crowned Kinglet, Swainson's Thrush, Philadelphia Vireo, Cape May Warbler, Black-throated Blue Warbler, Palm Warbler, Bay-breasted Warbler, Blackpoll Warbler, Connecticut Warbler, Wilson's Warbler, Dark-eyed Junco, Red Crossbill, and White-winged Crossbill.

Some of the species susceptible to forest fragmentation are relatively adaptable, even though they may be highly susceptible to fragmentation. Certain species, mostly passerines, may key into very small patches of suitable habitat within a large forest. For instance, the literature suggests that the Pine Warbler needs about 30 ha of mature pines. However, they will nest in predominantly deciduous woodlots with scattered mature pines, provided that the forest is large enough. This is true of many other species; a very small patch of a distinct habitat in a forest may attract species that would not be expected by examining Forest Resources Inventory or Ecological Land Classification mapping.

Table 41-1 summarizes the key habitat variables of breeding birds susceptible to forest fragmentation. Most of the information in the table is derived from data compiled by Steve Hounsell and Doug Magee of Ontario Hydro.

TABLE 41-1

GENERAL HABITAT REQUIREMENTS OF BIRD SPECIES VULNERABLE TO FOREST FRAGMENTATION

Potential Development Effects

Development may have major impacts on birds susceptible to forest fragmentation. Impacts may occur in several manners. The most obvious is direct habitat loss. This occurs when forest cover is removed or when houses, roads, or service corridors encroach into the forest. Species most at direct risk include any area-sensitive species when the total forest size declines below its threshold size, area-sensitive species that are obligate forest-edge nesters, and species that nest in the interior. The forest-interior species are most at risk, because the loss of a small amount of forest has the potential to result in loss of a disproportionately large amount of forest interior, or even complete elimination of this habitat. The impacts of development in different areas of forest are illustrated in the mitigation section.

Indirect effects include increased predation, parasitism, and disturbance. These effects may be more significant over the long term, resulting in slow population declines until species are eventually extirpated from the forest.

Forest fragmentation results in a smaller block of habitat, which facilitates nest location by predators and parasites. Fragmentation also increases edge, which favours common, generalist species, many of which are direct predators of nesting birds. Predators fall into two groups: birds and mammals. Predatory birds include edge species such as Blue Jays, American Crows, and Common Grackles. Primary mammalian predators include Virginia opossum, gray squirrel, eastern chipmunk, striped skunk, racoon, coyote, red fox, and domestic cat. Most of the edge bird species are more abundant and have more broods annually, and may be direct competitors for resources with forest-dependent species. With this suite of predators, both nests on the ground and low in the canopy are at risk of predation.

Creation of edge or corridors through forests facilitates nest-finding by the Brown-headed Cowbird. This species is an obligate nest parasite which lays its eggs in the nest of other birds. The host bird often raises the cowbird young at the expense of its own. Bird species nesting in the open or at edges have adapted strategies for combatting nest parasitism. Many forest birds have been exposed to parasitism only recently, and have not evolved mechanisms for reducing impacts of parasitism. Consequently, the entire annual reproductive effort may be lost  and populations may decline or even disappear over the long term.

A few of the species, mostly nonpasserines, are susceptible to human disturbance. These include some of the hawks and owls, plus the Ruffed Grouse, which may experience increased hunting pressure.

Development on adjacent lands may have impacts on species in this guild. The activities of humans and their pets in woodlots adjacent to developments reduces breeding success of some species and eventually leads to a loss of bird species diversity. Some of the area-sensitive bird species that nest on edges also require adjacent open habitats. If these areas are developed, they may be adversely affected. Heavy human usage of forests results in loss of forest structure. Different bird species are attracted to each level in the forest, so a loss of forest structure may reduce bird species diversity.

Table 41-2 summarizes the susceptibility of species in this index to indirect effects of development. All are susceptible to direct habitat loss and reducing forests sizes to below the area that they usually require. In the table, the column on human disturbance refers to people walking through the woods and not forestry practices or other activities that may alter forest structure.

Forest thinning and harvesting, and removal of trees considered hazardous to humans (i.e. loss of forest structure) can be detrimental to many species. Those most at risk are those that require mature forests, large trees for nesting or roosting, that hunt in the understory where there is a minimum of shrubs and saplings, and that require snags. Forest thinning can make the forest more attractive to deer, and they can decimate the understory and shrub layer.

One of the more insidious effects of forest fragmentation is the decline in the amount of forest habitat within the landscape. Once a landscape is less than 30% forested, forest-dependent bird species start to disappear. The first to disappear are those that require very large forested tracts and those that nest in forest interior habitat. Once the amount of forest habitat declines to 15 to 20% of the landscape, about 20% of the forest-dependent bird species will have disappeared. If forested habitat declines to as low as 5%, about 80% of the forest-dependent bird species will have disappeared.

TABLE 41-2

SUSCEPTIBILITY TO INDIRECT IMPACTS OF DEVELOPMENT

Mitigation

It may be difficult to totally mitigate the effects of development on populations of forest-interior birds. Any site alteration which results in an opening in the forest canopy will allow the woodland to be invaded by aggressively competitive birds from the forest edge and surrounding open areas. Even temporary roads traversing woodlots can have lasting impacts on these birds.

The optimum method is to determine which species are most sensitive to development and design the project to protect these species. If this is accomplished, most other species of concern should be protected. The area of the woodlot should not be decreased below the minimum size required for the most area-sensitive species.

Development should not occur in the interior of forests supporting species susceptible to forest fragmentation. If development is planned that will encroach into the edge of the forest, impacts on the amount of forest-interior should be determined. If significant amounts of forest interior will be affected, it may not be feasible to develop into the edge of the forest. By carefully looking at the shape of the forest, it may be possible to identify areas where encroachment into the forest may occur without affecting forest interior.

There may be instances where the woodland supports area-sensitive species that nest on the forest edge. Some of these may require adjacent open areas during the breeding season. In these instances, it may be necessary to leave a buffer of open area between the forest and the development.

Development could possibly be clustered instead of having houses dispersed throughout the forest or around it.

The size and shape of many woodlots can be improved by tree planting to increase the amount of forest interior. The benefits of this management practice are likely to take several years to be realized.

The following figures demonstrate potential development effects and mitigation techniques.


Index #42 - Woodland/Forest/West Virginia white butterfly/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 42

Habitat Type: 	Woodland/Forest

Species Group:  	West Virginia white butterfly [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Like most butterflies, the West Virginia white has very specific habitat requirements for the  completion of its life cycle. Moist deciduous or mixedwood forests with riparian features are preferred habitat. The presence of toothwort plants (Dentaria spp.) is an absolute requirement in their life history.

Adult butterflies emerge from chrysalises in the spring where they forage in the forest understory on the nectar of toothwort, trillium, and Canada violet flowers. Eggs are laid singly on the undersides of host plant leaves. Toothworts (Dentaria diphylla, D. laciniata, and possibly their hybrids) are the only plants known to be consumed by caterpillars. Larvae feed until early summer. The West Virginia white overwinters as a pupa buried in the leaf litter near host plants.

Preferred habitat is composed of moist, mature deciduous (maple/beech) forests containing riparian features and the herbaceous plants of the genus Dentaria (toothwort).

Potential Development Effects

Development planned for moist maple/beech forests in southern Ontario can affect preferred habitat of West Virginia white butterflies. Since the species is only active as an adult in the spring and early summer, care should be taken when scheduling  inventories in habitats likely to contain these rare butterflies so that their presence is not missed. Any moist deciduous woodland in southern Ontario with the host plant Dentaria (toothwort) should be considered as potential West Virginia white habitat.

Site alterations associated with multi-lot developments which affect patches of host plants will eliminate the function of the area for this species. Forest clearing, dredging, and excavation (any of which may alter the moisture regime of forest soils) present the greatest risks to species loss.

Development on land adjacent to woodlots functioning as preferred West Virginia white habitat is not expected to affect these butterflies unless it results in changes to the hydrology of this significant wildlife habitat.

Forest cutting and lot-clearing activities can have considerable direct effects on West Virginia white butterfly habitat. Opening the forest canopy will reduce the habitat suitability of the site for the host plant Dentaria (toothwort). Toothworts are shade-tolerant species that decline in vigour or even die if they are exposed to too much sunlight. If these host plants are lost from the plant community of the altered forest then West Virginia whites will become locally extinct. Larvae cannot switch to another host plant. Another threat associated with opening up the canopy or fragmenting the forest, is that the introduced cabbage butterfly may compete with the West Virginia white for the host plants. The cabbage butterfly avoids forest interior, but may penetrate a short distance into the forest. Another problem may be deer. As the forest opens, deer tend to use the forest more and may eat the host plant along with other understory and shrub species. In the case of large developments, there may be pressure to eliminate deer hunting, which is the only limiting factor to deer populations in southern Ontario.

Excavation and draining, even on adjacent land, pose considerable risks to West Virginia white butterflies. Any changes to the hydrological function of the woodland area which causes a negative change in soil conditions for host plants will lead to the loss of West Virginia whites from the area.

Mitigation

It is best to identify the host plant (toothwort) during inventories early in the planning process and plan to avoid this habitat during development. No site alterations or construction should take place in or adjacent to this habitat that will affect the moisture level of the forest stand and jeopardize the survival of the toothwort.

Mitigating the effects of development on preferred West Virginia white butterfly habitat is probably not possible owing to the highly specific habitat requirements shown by this species. Any change in the area's hydrology presents a very real risk to these butterflies.

Forests supporting populations of West Virginia whites and toothworts should not be thinned excessively or fragmented to the point where toothworts disappear or cabbage butterflies out-compete West Virginia whites.


Index #43 - Woodland/Forest/Reptiles/Habitat of Species of Conservation Concern/Preferred Habitat swh_hscc
Index # 43

Habitat Type:	Woodland/Forest

Species Group:  	Reptiles: eastern massasauga rattlesnake [THREATENED], eastern hognose snake [VULNERABLE], black rat snake [THREATENED]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat:	Preferred Habitat

Habitat Function and Composition

Woodlands function as preferred habitat for this group of reptiles. Forests provide the cover necessary for protection and shelter. The snakes of this group are predatory and depend on species which inhabit forests as a food source (i.e. rodents, small ground-nesting birds, amphibians). The black rat snake is arboreal and may also prey on bird eggs and nestlings in the canopy. All these snakes depend on abundant prey populations for their survival.

These species do not do well in areas frequented by people. This is due, in part, to the persecution they suffer at the hands of people intent on killing them. Woodland habitats must be large to ensure minimal contact with humans.

Reptiles which prefer woodlands use a variety of forested habitats. Forests which have abundant downed woody debris and other understory structures are most valuable since they tend to house abundant and productive populations of invertebrates, small mammals and birds that make up the food of this species group. Because these reptiles use a variety of forested (and at times non-forested) habitats, linkages to other habitat patches are needed to allow reptiles to move safely among them. For example, the massasauga hunts primarily in low, swampy woodlands while the black rat snake prefers upland forest and feeds frequently in trees on small birds. The black rat snake winters in rocky outcrops and then must travel to its summer forest feeding habitat.

Water is an important element in the lives of these reptiles. Rivers, creeks, ponds, shoreline areas, and wetlands need to be accessible to reptiles using woodland habitats.

Potential Development Effects

Development will affect the functions of preferred woodland reptile habitat if associated site alterations reduce the amount of forest cover available, resulting in a less structurally complex understory, or if wetland areas become isolated from forest cover.

Altering the structure and composition of the forest canopy or understory will ultimately affect food availability owing to reductions in populations of small mammals, ground-nesting birds, amphibians, and  invertebrates. As food availability is reduced, reptiles will have to spend more time searching for it. This places them at greater risk of predation. Small isolated populations are vulnerable to increases in mortality and this may affect their long-term viability.

Building and road construction which results in a barrier to movement to and from woodland and wetland environments will significantly affect the function of woodland reptile habitat. Forest stands that become isolated from wetlands may no longer function as preferred habitat. Increased road traffic presents considerable risk of mortality when snakes cross them or when they stop to rest on pavement taking advantage of the heat it provides.

Subdivisions which result in a large increase in human activity in woodland habitat present considerable risks to reptile populations. Lot-clearing activities will reduce food availability. Most significant is the fact that people are generally intolerant of the presence of snakes, particularly poisonous varieties. Although illegal, a certain amount of killing to control snake numbers will occur. Sometimes these snakes will end up in back yards searching for food or when they are travelling between habitats, or when they are basking in the sun. Increases in human activity will usually result in declines in reptile numbers.

Development on adjacent land should have little impact on the habitat of woodland reptiles provided it does not isolate a small woodland area from surrounding habitat.  Some mortality may occur through contact with people either through intentional killing or by accident on roadways.

It is very difficult to study snake populations because individuals are very unobtrusive. The presence of species is often overlooked entirely. Thus, it should be assumed that these species are present if the habitat is suitable and that the proposed development site is within the general range of the species. The habitat requirements of these and other species are poorly known, and they may require much larger areas than is generally thought. Radio-tagging studies of black rat snakes demonstrated that these animals often moved considerable distances among key habitats within their home range. Similar studies on the blue racer on Pelee Island showed that these snakes had home ranges as large as 200 ha. When large snake species are involved, careful consideration must be given to the impacts that development may have. The eastern massasauga and the black rat snakes are threatened species in Ontario. According to Policy 2.3 of the Provincial Policy Statement, no development is permitted within the significant portions of the habitat of these species. Significant portions of the habitat may include hibernacula, nesting areas, sites used for thermoregulation, feeding areas, and corridors among these critical habitats. In most instances, simply setting aside woodlands will not be sufficient to maintain populations of these species. A complete understanding of the life history requirements of the species on a site-specific basis will be necessary before impacts on the population and appropriate mitigation measures may be identified. The Ministry of Natural Resources must be contacted when proposed development may affect the habitat of these species.

Mitigation

Mitigating the effects of development on woodland reptile habitat involves consideration of the woodland/wetland connection and all aspects of their seasonal habitat needs, increased mortality due to human disturbance, and reductions in food supply owing to changes in forest composition and structure.

Steps must be taken to ensure that woodlands and wetlands do not become disconnected. This may require provision of a number of habitat corridors (woodland strips). The understory of these corridors should be as complex as possible having an abundance of downed woody debris, stumps and shrubs. Structures that provide hiding cover allow greater survival.

Increases in human activity within woodland habitat should be prevented when possible. Development should be designed so that it does not encourage additional human usage of forested habitat. Restrictions on lot clearing should also be considered. Owing to the nature of the woodland snakes in this group (i.e. large, threatening in appearance, and one is poisonous) human/reptile conflicts will be frequent and will likely create great tension for some residents. Public education programs designed to make residents aware of the habitat needs of these snakes, their behaviour, and steps people can take when they encounter these snakes will be necessary. However, the reality is that public education programs may not be effective in reducing the destruction of snakes.

It is best to leave a large block of habitat that is totally undisturbed rather than allow lot development throughout the entire woodlot. In that all of these snakes are vulnerable or threatened, an Impact Assessment will have to be very thorough if it is to demonstrate that any of the forested habitat may be developed without having a negative impact on the habitat of these species. Development should be clustered in as small an area as possible.

Roads should not be built near critical habitat, nor should they intercept routes that are likely to be used by snakes to travel from one required habitat type to another.


Index #44 - Woodland/Forest/southern flying squirrel/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 44

Habitat Type:	Woodland/Forest

Species Group:  	southern flying squirrel [VULNERABLE]

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

Southern flying squirrels are found in many locations in Ontario, often in the same woodlots as northern flying squirrels. Southern flying squirrels are not particularly numerous anywhere in the province but their greatest numbers occur in Carolinian remnant forests near the shores of Lake Erie. This species builds nests in hollow trees taking advantage of cavities created by wood heart rot and holes excavated by woodpeckers. Mature deciduous forests which produce abundant mushroom, tree seed, and nut crops are prime habitat for these squirrels.

For a woodlot to function as southern flying squirrel habitat it must be composed of mature hardwoods (particularly maple, American beech, and oak). Woodlots need to be large to provide enough habitat for more than a few squirrels (i.e. > 20 ha). An abundance of large (> 20 m tall) trees with advanced heart rot are needed to provide nest sites.

Potential Development Effects

Development which reduces the size and composition of mature and old-growth deciduous woodlots has the greatest potential to impact southern flying squirrel populations.

Tree cutting and lot-clearing activities which remove old, hollow trees effectively reduce the availability of nest sites. Without suitable nest sites this species is not able to breed successfully. If forests are greatly thinned in the process of development, then food resources will be diminished. Tree cutting is the most significant site alteration expected to negatively affect southern flying squirrel populations. The primary concern is over the removal of old decrepit trees which serve as nest sites. Removal of mature hardwoods, particularly nut-bearing trees like oak and beech, will reduce food supplies. This has a direct effect on the number of flying squirrels which can occupy the woodlot.

Reducing the size of the forest may make it unsuitable for southern flying squirrels. This will reduce the carrying capacity of the forest, and populations size may decline to the point where it is no longer capable of maintaining itself.

Increases in human activity within woodland areas may negatively affect southern flying squirrels by allowing the more human-tolerant gray squirrel to increase in numbers in the area. Increased competition for remaining food resources and tree cavities will affect flying squirrel populations. The gray squirrel is more adaptable and prolific. It may take over southern flying squirrel nesting and roosting cavities, and feeds on the same resources.

Development on adjacent land is not expected to affect flying squirrel populations, unless large trees are removed to reduce hazards to humans using the woodland. However, increased human activities and presence may result in an increase in gray squirrel populations. Winter bird feeding by humans results in an increase in gray squirrels, and shooting them is generally prohibited in developed areas. Increased populations of cats may also be detrimental to southern flying squirrel populations.

There are a number of limiting factors which have resulted in the southern flying squirrel being designated vulnerable. The most significant of these are habitat fragmentation, changes to forest structure, and increasing populations of gray squirrels.

Habitat fragmentation may affect southern flying squirrel populations in three way: residual woodlots may become too small to support a viable population; woodlots may become isolated so that flying squirrels may not be able to re-colonize woodlots where populations have become locally extirpated; and smaller woodlots are more likely to be inhabited by gray squirrels.

Mitigation

One major problem is that presence of southern flying squirrels is very difficult to determine. Even the most thorough inventories are likely to overlook this species. If its presence is not detected, then the Impact Assessment will not address the habitat requirements of this species. Another problem is that it is difficult to distinguish between the northern and southern flying squirrels. However, the two species have similar habitat requirements and limiting factors. If an unidentified flying squirrel is discovered during an inventory and the site is within the known range of the southern flying squirrel, it should be assumed that the more sensitive species is present.

There are a number of techniques that are not usually used during inventories that may be employed to try and find out if southern flying squirrels are present. A simple one is to tap trees and snags throughout the woodlot that have cavities in them. Unlike gray squirrels, which usually remain tight within the cavity when this is done, flying squirrels usually glide out of the cavity. Another technique is to “jack-light”. Flying squirrels have very large eyes that reflect light at night, and their presence can often be determined with a flashlight at night. Using this technique, it is unlikely that it will be possible to determine which species of flying squirrel is present. Mist-netting at night is an effective technique for capturing flying squirrels. This has the advantage that the observer will have the animal in hand and can make a positive identification. Ancillary benefits are that bats and owls, other difficult-to-detect species, may also be caught in the nets. Mist-netting should only be done by people experienced in operating mist nets. Permits will be required from the Ministry of Natural Resources to collect small mammals and it may also be necessary to get a permit from the Canadian Wildlife Service if migratory birds may be caught in the nets. Ideally, any mist netting would be conducted by a licensed bird bander. One final potential inventory technique is to set up a bird feeder. Flying squirrels readily come to bird feeders at night.

The above inventory techniques may be expensive and may still not detect the presence of southern flying squirrels. The best mitigation is to assume that southern flying squirrels are present if the habitat is even marginally suitable. If this is done and their habitat is protected, there will be no need to conduct special inventory techniques. However, if encroachment into suitable habitat for southern flying squirrels is planned, the inventory should demonstrate as conclusively as possible that either the southern flying squirrel is absent or, if it is present, that development will not have negative impacts on it.

Mitigating the effects of development on southern flying squirrel populations involves ensuring that as little of the existing woodlot area is affected as possible. This may involve clustering of development near one edge of the woodlot or keeping development out of the woodlot. This is more favourable than allowing development to be dispersed throughout the woodlot or clustering development in the centre of the woodlot.

Lot-clearing activities should be controlled so that the density of mature trees is not reduced any more than needed to fit essential structures into the site. Reducing tree density will ultimately reduce food availability. Provision should be made to allow old, decrepit trees to remain in place since these serve an important ecological function. It is important that mature trees be allowed to age to replace the old nest trees which will eventually fall.

Tree planting to compensate for the loss of woodlot area is not a viable option. The time involved in developing a suitable mature hardwood forest would be much too long to reasonably expect the stressed population (i.e. the population forced to occupy a smaller, less productive forest) to persist. In other words, the local population may not survive long enough for its members to move into the “manufactured forest”.

Nest boxes may provide additional nesting and resting areas for southern flying squirrels. They readily use Wood Duck boxes. This has not been implemented as a management technique for flying squirrels. For areas where gray squirrels are common, the diameter of the cavity entrance should be designed so that it allows access for flying squirrels but not gray squirrels. Gray squirrels often chew and enlarge cavity entrances, so tin or some other deterrent to chewing should be put around the cavity entrance, but this will have to be designed so that it does not preclude entrance by flying squirrels. Nest boxes for flying squirrels are not a proven management technique, so any Impact Assessment that is relying heavily on this as a management technique should first demonstrate that flying squirrels will use them. Another problem often associated with nest-box programs is that they require regular maintenance. If nest boxes are part of the mitigation, the proponent must demonstrate that there is a strong commitment to maintaining the nest boxes.

Development should not reduce forest size below the 20 ha that is considered the minimum to support a population of southern flying squirrels. In many cases, due to other limiting factors in the woodland, 20 ha may not be sufficient. Whenever development is proposed that will directly affect southern flying squirrel habitat, the proponent should demonstrate that the proposed reduction in habitat size will not negatively affect southern flying squirrel habitat.


Index #45 - Woodland/Forest/Woodland Raptors/Habitat of Species of Conservation Concern/Breeding Habitat
Index # 45

Habitat Type: 	Woodland/Forest

Species Group:  	Woodland Raptors: Sharp-shinned Hawk, Cooper’s Hawk, Northern Goshawk, Red-shouldered Hawk [VULNERABLE], Broad-winged Hawk, Barred Owl, Boreal Owl, Northern Saw-whet Owl

Significant Wildlife Habitat Category: 	Habitat of Species of Conservation Concern

Functional Habitat:	Breeding Habitat

Habitat Function and Composition

The birds in this index nest and hunt for prey in forested habitat. There are other raptor species that nest in woodlands but hunt in open habitat. They are less dependent on woodlands for survival, and many are edge species that are not vulnerable to the same stresses as true woodland raptors. Most woodland raptors have highly specialized habitat requirements and may be vulnerable to apparently minor changes in habitat. Forests provide the cover necessary for woodland raptors to find shelter, build nests and hunt for prey. As a group, they are evolved to hunt and manoeuvre swiftly within the forest canopy and understory. Forests provide the small mammals, birds, amphibians, and reptiles these species need to feed their offspring.

Many woodland raptors are strongly territorial with individuals defending their space. It is not uncommon for them to use the same territory for a number of years. Home ranges are much larger than defended territories. Even in ideal nesting habitat, nesting raptors tend to be widely spaced, seldom nesting closer than a kilometre to each other, although this varies by species. Most species in the group build new nests each year in traditional nesting areas, but some use the same nest year after year. These birds may build or repair more than one nest in their territory but they only lay eggs in one of them.

Many species in this guild have suffered from forest fragmentation across southern Ontario due to their dependence on larger tracts of continuous forest cover. Woodland raptors are normally intolerant of human disturbance and consequently they require a high degree of seclusion from most forms of human activity. Nest-site disturbance is particularly of concern owing to its impact on brood survival and hence population density and stability.

The following table provides a summary of the key habitat requirements of woodland raptors. Important habitat characteristics include forest type and size, nesting tree species and characteristics, use of alternate nests, nest-site and territory fidelity, spacing of pairs, understory density, and prey.

Species	Habitat Characteristics
Sharp-shinned Hawk	Nests almost exclusively in coniferous forests, seldom in mixedwood stands; preferred forests are very dense, with 80% or more canopy cover, are even-aged, and typically 25 to 50 years old; plantations are frequently used; it nests in upland and lowland stands, but appears to prefer wetlands or areas near lakes or watercourses; nests are usually at the edges of forest; forests larger than 30 ha appear to be preferred; usually nests in spruce, hemlock, cedar, or pine; most nests are 6 to 10.5 m from the ground, usually at the trunk a few metres from the top of the tree; selects trees with particularly dense crowns in areas of high tree density; usually builds a new nest every year, but almost always within 100 m of the previous year's nest, even if another pair is involved; territory size is about 4 ha, but home range may be 200 to 1300 ha; nests tend to be spaced 1.8 to 6 km apart; foraging usually occurs in the upper canopy; eats primarily small birds which are caught in flight
Cooper's Hawk	Nests mostly in deciduous forests, less frequently in mixedwoods; in western North America, it often nests in coniferous plantations and even in cities; in Ontario, it is usually associated with forests 50 ha in area or larger, but may occasionally use woodlots as small as 4 ha or even smaller; tends to nest in intermediate-aged and mature forests; prefers upland forests; tends to nest in forest interior; requires a canopy height of at least 15 m; nests are often within 300 m or less of water; about 70% of Ontario nests are in deciduous trees; preferred species are maple, beech, and hemlock; most nests are 9 to 13.5 m from the ground; nests in conifers are usually in upper branches against the trunk, nests in deciduous trees are mostly on horizontal, forked branches; territories are used traditionally, with a new nest usually being built within 100 m of the previous one; the territory size is 6 to 50 ha, but the home range is 200 to 1800 ha; nests are spaced about 1.8 m apart, rarely as close together as 700 m; hunts at the edge of forests and in forest openings; eats mostly small birds which are caught in flight
Northern Goshawk	Nests in mature deciduous, mixed, and coniferous forests, including plantations; inhabits closed-canopy forests with few shrubs or saplings in the understory, avoids areas with dense shrubs; nests mostly in forests 100 ha in area or larger; nests in the interior; most stands used for nesting are 100 or more years old; prefers stands with many conifers, but seldom nests in them; 70% of Ontario nests are in deciduous species; preferred species are birch, pine, poplar, beech, and maple; nests are at a main crotch or forks in branches at the trunk; most nests are 9 to 12 m from the ground a short distance below the crown of the tree; selects the largest trees available for nesting; may build a new nest every year or use one for 2 or 3 years; may have alternate nests sites 60 to 400 m away; territory size is 5 to 10 ha, but home ranges are at least 200 ha; nests average over 5 km apart, occasionally as close together as 2.4 km; hunts in flight under the forest canopy; feeds on medium-sized birds and mammals; important prey are Ruffed Grouse and snowshoe hare
Red-shouldered Hawk	Nests mostly in mature mixed and deciduous forests, occasionally in pine plantations; lowland forests are preferred; requires a closed canopy (>70%) with a minimum of shrubs and saplings; appears to prefer forests larger than 100 ha, but occasionally nests in smaller stands; tends to nest in the interior; presence of nearby water is essential; nests in stands 100 to 200 years old; almost all nests are in deciduous trees, with beech, maple, and yellow birch being preferred; most nests are 11 to 16 m from the ground in tree forks or main crotches of branches; the nest tree is usually larger than average in the stand, and often extends above the canopy; usually selects trees with a dbh of 50 cm or greater; the nest is usually at the bottom of the canopy or below it; has a very high site-tenacity for the territory; territories and home ranges coincide and are about 60 ha in area; nests may be as close together as 900 m; hunts from a perch in the forest or along a forest clearing; about half of the diet is amphibians and snakes; also eats voles and shrews
Broad-winged Hawk	Nests mostly in mature, dense mixed and deciduous forests, less frequently in coniferous stands and plantations; prefers lowland stands or forests that are close to swamps or open water; appears to prefer forests 100 ha in area or larger; nests are often at the edge of forests or near an opening; prefers stands with a canopy height of 21 m or more; nests are usually on a slope in a live deciduous tree; preferred nest tree species are birch, poplars, maple, oak, and pine; most nests are 7.5 to 12 m from the ground; usually builds a new nest each year; prefers trees with a dbh >45 cm; territory and home range appear to be the same, and are 100 to 200 ha in area; there is a high rate of homing to territories, but birds tend to nest 100 to 400 m from the previous nest; hunts from a low perch such as a tree, fence post, or power line; less dependent on forests for hunting than many others in this guild; hunts on edges and in clearings when it does hunt in forests; eats mostly amphibians, insects, and meadow voles
Barred Owl	Nests in mature deciduous and mixedwood forests; rarely uses pure coniferous stands; needs large numbers of trees larger than 50 cm dbh; inhabits both upland and lowland forests; avoids edges and nests in the interior; needs very large forests 100 to 400 ha minimum size; may prefer water near the nesting area, but it does not appear to be essential; is an indicator of old-growth forest; requires forests with few shrubs and saplings in the understory; nests mostly in natural cavities, but occasionally on old stick nests or squirrel drays; all reported nests in Ontario have been in deciduous trees: balsam poplar, beech, and white birch; most nests are 7.5 to 10.5 m from the ground; nest trees are usually dead or decadent; has a home range of about 250 to 800 ha; in ideal habitat, nests are at least 2 km apart; has very high nest-site and territory fidelity; territory boundaries remain the same even if different owls are present; hunts mostly in swamps from a perch, but also in marshes and meadows; eats mostly voles, cottontails, and hares, but also some squirrels, amphibians, turtles, small birds, and insects
Boreal Owl	Nests in extensively-forested areas, including the Boreal Forest Zone and the northern portions of the Great-Lakes St. Lawrence forest; nests mostly in mature mixedwood stands of spruce, tamarack, balsam fir, trembling aspen, and white birch; often associated with forest openings, particularly bogs and beaver meadows; avoids pure coniferous stands; nests in natural cavities and those excavated by Northern Flicker and Pileated Woodpecker; most nests are in live trembling aspen, occasionally in dead aspens; most nests are 10 to 15 m from the ground; territories are 2 to 5 ha in area, but home ranges are 100 to 500 ha; presence of suitable nesting cavities is a significant limiting factor; hunts mostly from a perch in forest; red-backed voles are a staple in the diet, but other small mammals, birds, and insects may be eaten
Northern Saw-whet Owl	Nests in upland and lowland deciduous, mixed, and coniferous stands, with a slight preference for stands containing conifers; requires intermediate-aged to mature stands; forest size is not important; appears to be most abundant in coniferous and mixedwoods with a well-developed middle canopy of conifers 2 to 4 m tall; nests in natural and woodpecker cavities; most nests are in live deciduous trees; most nests are 3.5 to 6 m from the ground; home range and territory sizes are not well known; home ranges may be about 150 ha; hunts from perches in forest clearings or along forest edges; eats mostly small woodland-dwelling mammals such as deer and white-footed mice, red-backed voles, woodland jumping mice, and small shrews; also eats other small mammals, preferring prey that does not weigh much more than 40 g; may eat small numbers of birds and insects
Potential Development Effects

Development can have tremendous impacts on the breeding habitat of woodland raptors. Site alterations which reduce the availability of forest cover effectively remove productive habitat from the territory of resident breeding pairs. Depending on the size of the area affected and the overall availability of woodland habitat, there may be a significant reduction in the amount of food available to feed offspring. This in turn affects brood rearing success, impacting population growth and the long-term persistence of woodland raptors. Forest fragmentation or decreasing forest size can have adverse effects on species such as Sharp-shinned Hawk, Cooper's Hawk, Northern Goshawk, Red-shouldered Hawk, and Barred Owl. All of the raptors in this guild have large home ranges and require large areas to hunt in. Prey populations fluctuate annually, and any loss of habitat for the raptors or their prey may result in a decline of woodland raptors or their local extirpation from a woodlot.

Tree cutting within woodlands can reduce the habitat suitability for some raptors. Loss of mature trees may result in loss of existing or potential nest sites. Tree cutting can also promote regeneration. This makes hunting much more difficult for species such as Northern Goshawk, Red-shouldered Hawk, and Barred Owl. Tree cutting may also make the habitat more suitable for competitive edge species such as the Red-tailed Hawk which may displace the Red-shouldered Hawk.

Development may affect wetland habitat or woodland pools by discharge of stormwater or drying due to reduced infiltration. This can reduce prey availability for species that consume many amphibians, such as the Red-shouldered Hawk. Most raptors require more than one habitat type within their home range to satisfy their nesting and foraging needs.

Removal or forest-floor debris, such as logs and limbs, can reduce cover for small mammals and amphibians. This may result in fewer prey available for some species. Removal of hazardous trees may result in the loss of suitable nesting cavities for some species such the three owls in this guild.

Development in the vicinity of nesting habitat may cause birds to abandon the area, particularly if development increases the level of human activity in the area. Frequent disturbance can lead to nest abandonment. Once displaced, a breeding pair will have to seek other suitable nest sites within their territory. If none exist, they will have to compete with other birds for access to suitable nesting sites. Only birds successful at defending nesting sites will breed. The end result is a reduction in nesting habitat within the area and ultimately a reduction in raptor numbers. Because the nests of most species are spaced considerable distances apart, the loss of one nesting territory probably means that one less pair will breed.

Development on adjacent lands may have considerable impact on breeding habitat if it results in an increase in human activity within the pair's territory. Intrusions into the traditional nesting habitat during the nesting season may result in birds abandoning the site. Increased human activity and site alterations which affect food availability, or which simply prevent raptors from foraging in the area, may result in a reduction of accessible food within the territory to the point that brood survival is impacted. Birds cannot switch to new feeding sites since chances are they occur within the territories of other breeding pairs, or there may be no suitable habitat nearby.

Cats have the potential to compete with woodland raptors for small mammal prey.

Mitigation

Many woodland species do not adapt well to reductions in the size of forests and fragmentation of existing woodlands. Forest size and integrity should be protected as much as possible when planning for development. Forest sizes should not be reduced below the minimum forest size requirements of the most sensitive species present. Lots spaced throughout woodlots should be avoided. It would be better to cluster development in a few areas and preserve as much natural area as possible. Additional forest lands can be created through planting or allowing areas to grow back naturally. This is a slow process and is not suitable compensation for the loss of forest habitat since many species may be reduced to critically low numbers in the intervening time period. Local and regional extinctions may occur in the interim and new habitat may not be colonized in the future.

Mitigating the effects of development on woodland raptor breeding habitat involves preventing the loss of forest cover, maintaining the existing forest strucutre, and ensuring that increased human activity does not occur near nests during the nesting season.

Lot clearing and construction should be directed as far away from existing nests as possible. Given the importance of nest sites and the way raptors use perches located in surrounding habitat, a buffer extending at least 200 m from active nests, where no development is allowed may be required to prevent the loss of nesting habitat function. This is particularly important for species that tend to build new nests a distance from the previous year's nest.

To ensure a continued supply of nest sites, consideration should be given to protecting local areas around inactive raptor nests. Raptors may  reuse these old nests and nest trees from time to time and these sites should be protected so that alternative nest sites are available and well distributed throughout the landscape.

The structure of the forest is extremely important to many woodland raptors. Removal of mature and decadent trees and snags should be avoided. Forest-thinning activities that are likely to promote sapling and shrub growth should be avoided when species such as the accipiters, Red-shouldered Hawk, or Barred Owl are involved.

Appropriate stormwater management will be required to ensure that woodland pools and wetlands and the amphibians they support are not adversely affected. If these aquatic resources are dependent on groundwater, it should be demonstrated that development will not have negative impacts on groundwater quality or quantity which could ultimately affect raptor prey populations.

All of the habitats required by a pair of nesting raptors should be identified and protected. Any loss of a habitat or prey resource within a home range may result in the loss of the birds.

Raptors are generally not adaptable to new habitat conditions. For instance, some Cooper’s Hawks nest in urban areas in western Canada. Cooper’s Hawks nesting in natural habitat or plantations in southern Ontario are highly unlikely to continue to nest if their habitat becomes urbanized. Raptors are particularly vulnerable to changes in habitat because they tend to return to the same area to nest year after year. They may do this even if the habitat has become unsuitable to the point where nesting birds do not raise a brood. In Waterloo Region, Red-shouldered Hawks continued to return to traditional nesting sites even after the forests in which they nested were reduced to areas as small as 4 ha. Eventually, the Red-shouldered Hawk was temporarily extirpated from the Region of Waterloo as a result of forest fragmentation, but has recently reappeared as a result of more forest cover than was present in the late 1960s and early 1970s.


Index #46 - Woodland/Forest/Amphibians/Movement Corridor/Woodland Movement Corridor
Index # 46

Habitat Type: 	Woodland/Forest

Species Group:  	Amphibians: red-spotted newt, Jefferson salamander, blue-spotted salamander, spotted salamander, smallmouth salamander [VULNERABLE], American toad, gray tree frog, spring peeper, chorus frog, wood frog, leopard frog, pickerel frog, green frog

Significant Wildlife Habitat Category: 	Movement Corridor

Functional Habitat: 	Woodland Movement Corridor

Habitat Function and Composition

Most amphibians require a source of water to reproduce. During spring, these species concentrate in woodland ponds to mate and lay eggs. Eggs are laid in water where they hatch as larvae. The larvae live in the water for varying lengths of time depending on the species, and eventually emerge as adults. The red-spotted newt is an exception in that the larvae live on land for several years, returning to woodland pools to live as adults. Adults of other amphibian species either live in the pond or at its edge, or disperse to live in terrestrial habitats. Those that do disperse usually return in the spring to breed or in the autumn to hibernate in bottom sediments. Others hibernate in soil or rotting logs located near breeding ponds. Woodland movement corridors are required to facilitate movement of amphibians to and from breeding ponds, to provide dispersal links to other nearby ponds, and to provide access to summer and winter habitat.

Corridors must provide suitable habitat for these species to use them. The forest canopy of the corridor must not be opened up to the point that there is a loss of moisture in the understory. The supply of downed woody debris and other structure on the forest floor needs to be maintained.

For a woodland pond to continue functioning as a breeding pond for amphibians it must remain connected to surrounding woodland habitat to facilitate movement between the pond and surrounding terrestrial habitats. Both elements are required by most amphibians to complete their life cycles. Therefore, the pond and surrounding woodland habitat are integral components which must both be retained to ensure no loss of breeding pond function.

Movement to and from woodland ponds is easily disrupted if barriers are created. Barriers need not be extensive to stop or divert amphibian movement. Amphibians, particularly salamanders, tend to move in bursts when conditions allow. The pattern that emerges is one of localized activity followed by long-distance travel, usually at night when it is raining or at least when relative humidity is high (i.e. foggy nights). Gaps in forest canopy and understories denuded of vegetation, downed woody debris and other structures providing hiding cover, can severely curtail movement. Wooded movement corridors which provide unbroken links to isolated ponds are key to retaining their function as breeding or hibernating ponds.

To function as movement corridors for many amphibians, wooded strips must be wide enough to provide an interior area of moist woods. The forest canopy should be closed (> 60 % crown closure) and composed of deciduous trees (species composition may vary). There may be gaps in the canopy but they should not bisect the corridor. The forest understory should have an abundant supply of downed woody debris, shrubs, and other structures providing cover and moist microclimates. Some amphibians will also cross open areas such as old fields, pastures, and hayfields.

Potential Development Effects

Development which results in the isolation of small woodland ponds from terrestrial woodland habitats will  disrupt the function of the pond and the surrounding land for amphibians. The loss of the breeding pond will affect the population dynamics of essentially all amphibian populations in the vicinity of the development. Development in woodland strips which link ponds to surrounding woodlands may also affect the function of breeding ponds.

Roads and other site alterations which create gaps in forest cover may act as barriers to movement to and from ponds. Busy roads built in forest cover acting as a link to amphibian breeding (and hibernating) ponds will result in increased mortality. Large numbers of amphibians are killed locally on highways and other roads when they are migrating among habitats used in different phases of their life cycle. High mortality in the vicinity of ponds may jeopardize long-term persistence of some amphibian populations. Amphibians are especially vulnerable to being killed on roads in the spring when they are migrating to breeding ponds, but warm roads are attractive for resting.

Tree cutting within woodland corridors acting as a link between the breeding pond and surrounding forest cover can disrupt pond functions if the forest canopy is opened up to the point that woods become dry or gaps bisect the wooded strip. Lot-clearing activity may severely impact corridor function if it results in the loss of considerable structure (downed woody debris, etc.) from the understory.

Mitigation

The effects of development on breeding pond functions can be made less severe by

ensuring that some forest habitat is left linking the pond to surrounding woodlands. Identifying critical components of amphibian habitat is very important early in the planning process.

Steps should be taken to ensure that forest cover remains intact around the breeding pond allowing seasonal movement to and from the pond. Woodland corridors should be relatively wide so that an interior of moist woods is provided. This is important since amphibians tend to move slowly through corridors, seeking cover and feeding habitat as they go. Therefore, corridors need to contain habitat features typical of woodland amphibian habitat in general.

Developments should be planned so that breeding ponds are identified and protected and that the linkages between ponds and summer range are maintained. Road systems should be designed so that they do not run parallel to breeding ponds or cut off migration routes between critical habitats. Culverts or underpasses may be required to permit passage of amphibians.


Inxdex #47 - Woodland/Forest/Reptile/Habitat of Species of Conservation Concern/Preferred Habitat
Index # 47

Habitat Type:	Woodland/Forest

Species Group: 	Reptile: wood turtle [VULNERABLE]

Significant Wildlife Habitat Category:	Habitat of Species of Conservation Concern

Functional Habitat: 	Preferred Habitat

Habitat Function and Composition

The wood turtle is the most terrestrial of all of Ontario’s native turtles. During summer they travel extensively in woodland and riparian habitats foraging on fruits, plant matter, mushrooms, earthworms, and other invertebrates. Much of their time is spent foraging in woodlands and riparian areas, although they will also use meadows and even agricultural land. Nests are constructed along the banks of clear rivers with sand or gravel bottoms. Adult wood turtles return to rivers in the autumn to hibernate in the bottom sediments of deep pools or in stream bank holes (often excavated by muskrats). The same hibernation sites are often used year after year, and they may be communal, with several turtles hibernating together.

For a woodland area to function as wood turtle habitat it must have a riparian association. Woodlots in the flood plains of rivers with sand or gravel substrates appear to be most valuable to this species. Wood turtles use a variety of forests but seem to prefer mixed forests with alders bordering streams in Algonquin Park, and maples and a variety of deciduous stand types in the south. Rivers are a key component of wood turtle habitat. They must be clear water, have gravel or sand substrates, and have a moderate current.

For nest sites, wood turtles prefers areas with considerable exposure to direct sunlight, well-drained but moist soil that is not subject to flooding, and a substrate without rocks or dense vegetation.

At night, wood turtles rest in sheltered areas of watercourses, or on land among sparse grass, leaves, or brush.

Home ranges are relatively small, and may be 5 to 25 ha in area, depending on habitat type and sex of the turtle. Most movements are along watercourses, rarely travelling farther than 150 m overland.

Potential Development Effects

Development will affect the functions of preferred wood turtle habitat if associated site alterations reduce the amount of forest cover available, result in a less structurally complex understory, or if suitable rivers (clear water, sand or gravel bottom) become isolated from forest cover.

Building and road construction which results in a barrier to movement to and from woodland and riparian environments will significantly affect the function of wood turtle habitat. Bridges may be a barrier if embankments are built right down to the water’s edge, or if forest cover is removed either side of the bridge. Woodland areas that become isolated from rivers no longer function as preferred habitat. A common problem may be to leave woods in steep valleys, but develop the forested tableland, or have large back lots extending right to the watercourse. This may result in the loss of critical wood turtle foraging habitat.

Subdivisions which result in a large increase in human activity in woodland habitat present considerable risks to wood turtle populations. Lot-clearing activities result in the loss of forest floor structure (downed woody debris, etc.) which reduces food availability. Most significant is the fact that pets and children often kill or injure wood turtles either intentionally or by accident. Many wood turtles have been collected as pets leading to reductions in local populations. Increases in human activity will usually result in declines in wood turtle numbers.

Development on adjacent land may affect wood turtle populations if it isolates a small woodland area from surrounding habitat.  Care must be taken to ensure that adjacent lands are not important feeding areas. Some mortality or loss of turtles from the population will occur through contact with people either through collecting, unintentional killing, or by accidents on roadways.

Factors that affect watercourse water clarity, substrate, or flows may be detrimental. Wood turtles require clear water, and increased sedimentation, erosion, or water turbidity may have adverse effects. Increased sediment loadings could also cover up the sand and gravel substrates that it prefers. Development that slows water flows, such as roads or other structures that partially impound water, may also affect wood turtle habitat. Wood turtles prefer water with moderate flows; slowing flows may also result in sediment deposition over preferred substrates.

In-stream work has the potential to affect nighttime roosting areas or wintering sites.

Because wood turtle populations tend to be small, local, and fairly sedentary, development has the potential to extirpate local populations. Once this occurs, it is highly unlikely that wood turtles will recolonize the area, even if the habitat is suitable.

Mitigation

Mitigating the effects of development on wood turtle habitat involves consideration of the woodland/river connection; increased mortality due to human disturbance; reductions in food supply owing to changes in forest size, composition and structure; and water quality.

For development in or adjacent to wood turtle habitat, the proponent should demonstrate a good understanding of the key habitat requirements of the turtles. Population size, feeding areas, nighttime roost locations, and winter hibernation areas should be known before decisions on the acceptability of the development are made. There should be no direct impacts on key habitats or on movement corridors among these areas. Mitigation may not be possible if the population is fairly small and isolated from other wood turtles. In these instances, increased mortality due to roadkill or human persecution may result in loss of the population even if habitat is not affected.

Steps must be taken to ensure that woodlands and suitable rivers (clear water, sand or gravel bottom) do not become disconnected. This may require provision of a number of habitat corridors (woodland strips). The understory of these corridors should be as complex as possible having an abundance of downed woody debris, stumps, and shrubs. These structures provide hiding cover and food allowing greater survival. Access to prime feeding areas, wintering habitat, and nighttime roosts must also be maintained.

Any instream work or structures should be designed so that they do not affect hibernation areas or nighttime roosts, or change water flows or substrate. Suitable sediment controls and maintenance of silt fences, etc. will be required for work near water.

Appropriate stormwater management will be required to ensure that an excess of sediments are not delivered to a watercourse that is wood turtle habitat.

Roads should be situated so that they do not intercept turtle movement patterns. If this is not feasible, underpasses should be incorporated to ensure safe turtle passage. It may be necessary to demonstrate that turtles will use such structures prior to full approval. Care should be taken that roadsides are not attractive nesting habitat for turtles, as this is likely to result in increased mortality.

New bridges should be designed to allow passage on land under the bridge. Ideally, bridges would be constructed of large spans so that riparian habitat was maintained and no fill was placed in the stream valley. Riparian and forest cover either side of the bridge should be maintained.

Increases in human activity within woodland habitat should be prevented when possible. Restrictions on lot clearing should also be considered. Public education programs designed to make residents aware of the habitat needs of wood turtles, their vulnerability to disturbance, and the significant impacts that collecting turtles for pets can have on local populations should be undertaken. However, educational programs are often limited in their effectiveness.

It is best to leave a large block of habitat that is totally undisturbed rather than allow lot development throughout the entire woodlot. Development should be clustered in as small an area as possible.

Stream systems and adjacent woodlands should be maintained. Because wood turtles may move as far as 150 m from watercourses to feeding areas, woodlands within 150 m of a watercourse that is functioning as wood turtle habitat should be retained unless an Impact Assessment can demonstrate that removal of portions of the woodland will not have negative impacts on wood turtles.


Index #48 - Woodland/Forest/white-tailed deer/Movement Corridor/Migration Trail
Index # 48

Habitat Type:	Woodland/Forest

Species Group:	white-tailed deer

Significant Wildlife Habitat Category:	Movement Corridor

Functional Habitat:	Migration Trail

Habitat Function and Composition

White-tailed deer migrate seasonally between summer and winter range (most people refer to winter range areas as deer yards). As they move to and from winter range they usually travel through forest habitat taking advantage of the cover it provides. The same migration trails are used year after year. The cover provided by the corridor is significant to deer since, as they move to yards, they must travel through unfamiliar territory. Movement through unfamiliar habitat is risky owing to the fact that animals do not know where dangers tend to lie, and are not familiar with escape routes. Continuous forest cover with an undisturbed understory provides the security that deer need for safe travel while migrating. The presence of movement corridors becomes more significant closer to deer yards since progressively more deer utilize them. Corridors should radiate out in all directions from yards to ensure movement of deer from all areas of the surrounding landscape. In many situations corridors provide protective cover for deer as they make forays to and from the yard to feed in nearby agricultural fields or on other food sources, such as acorns. Spring field-feeding opportunities on early grasses and forbs allow deer to begin to replenish energy supplies which have been depleted over the winter.

For an area to function as a movement corridor for migrating deer it requires specific habitat features. Deer establish migration trails in forest habitat, often using terrain features such as ridges and valleys. The species composition of forest cover in movement corridors varies but conifer species appear to be important. The structure of the forest is more significant to deer than its composition, with forest understory characteristics contributing most to function. The forest understory of corridors should be well supplied with shrubs of various species. There can be forest openings within the corridor but the size and number of openings should be small. This configuration of habitat will provide maximum cover and security.

Potential Development Effects

Creation of multiple lots has the potential to totally disrupt movement corridor function if a significant proportion of the corridor is affected. The greatest impact would occur when the forest cover of the corridor is totally bisected.

Since deer tend to use the same migration trails year after year, any structures which are placed in the corridor will be in the path of migrating deer. If the structures affect relatively little of the available forest cover of the corridor, deer will be able to pass by with less effect. As more of the width of the corridor is impacted, deer will have greater trouble avoiding buildings, fences, etc. As deer try to move through the subdivision they may become entrapped by fences, hit by cars, chased by dogs, or create problems for residents such as feeding on ornamental trees and shrubs. If a corridor is completely severed, deer may be forced to seek an alternate route to the yard and if alternatives are not available, they will have to winter in unfamiliar habitat. This poses considerable risk to deer. Increases in deer mortality are likely and may contribute to an overall decline in deer numbers in an area measuring 10 times the size of the yard that deer are migrating to. Suitable deer yards are in short supply and therefore deer often cannot simply move to another area.

Single lots may also affect migration trail functions. Most severe impacts are expected when the lot is located in the narrowest section of an already narrow (i.e. < 100 m) movement corridor.  As the width of the corridor declines, deer will have greater trouble avoiding buildings, fences, etc.

Site alterations which reduce the width of the movement corridor will have negative impacts on migrating deer. The greatest impacts are anticipated in situations where busy roads or residential areas are built so they must be traversed by deer as they travel to and from the yard. Loss of tree cover, and perhaps more significant, loss of hiding cover in the forest understory, can cause considerable difficulty for migrating deer.

Mitigation

The effects of any development proposed for deer migration trails can be made less severe by directing activity away from narrow sections of the forested movement corridor and planning projects so permanent structures do not bisect the corridor. The best approach to mitigation is to know the location of deer yards in the area and identify key movement corridors serving each yard. Development should be designed to maintain the integrity of the corridors (width, habitat complexity, etc.).

Residential developments pose the greatest threat to migrating deer largely due to deer encounters with fences, cars, and dogs. Subdivisions which specify that property fences are not permitted will allow unobstructed deer movement through the area. This would greatly reduce the frequency of deer entrapment. A ban on dogs should also be considered. Speed limits on roads traversing movement corridors should be reduced, at least during spring (March, April) and autumn (November - January) migration. Deer crossing signs placed in areas where deer are most likely to cross roads may reduce the frequency of deer vehicle collisions. Although these mitigation techniques may reduce the impact of a development on migrating deer, these measures are difficult to enforce. It is much more preferable to prevent impacts in the first place.

It may be possible to create an alternative corridor. However, because a forested corridor takes many years to grow and develop the structure needed for deer, in most cases it would not be feasible under the normal development time frame.


Index #49 - Woodland/Forest/black bear/Rare or Specialized Habitat/Unique Feeding Area
Index # 49

Habitat Type:	Woodland/Forest

Species Group:	black bear

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat:	Unique Feeding Area

Habitat Function and Composition

Outside of the denning season (mid October to mid April), black bears seek areas providing seasonally-abundant foods. They often make extensive movements (40 to 80 km) to get to these  unique feeding areas. During spring, bears seek forest openings and field edges where they can eat succulent new shoots of grasses and sedges. These highly digestible and nutritious foods help bears to replenish themselves from their long winter dormancy.

During summer, bears seek areas where fruit is abundant. Bears usually seek areas where blueberries are common, but also visit areas offering other berry crops (i.e. raspberries, pin cherries, service berries, apples, etc). During autumn, bears seek forest stands providing hard mast (oak and beech nuts).  Access to abundant berry and nut supplies is particularly important as bears must eat enough high quality food to allow them to build up the large fat reserves that they need to survive the winter.

During spring and summer, forest openings provide most of the foods that bears require. As snow melts in the spring and bears first start foraging they visit grassy areas where they are able to find succulent growing stems of grasses and sedges. During summer, bears will visit open areas providing raspberries and blueberries. In the fall, most bears seek forest ridges offering a supply of acorns. Bears will also seek stands of American beech, climbing the trees to eat beechnuts. Evidence of past use of maple/beech stands is displayed as easily-seen claw marks in trees and branches broken inward toward main branches forming a “bear nest” in the crown of large beech trees.

Potential Development Effects

Development has the potential to eliminate some unique feeding areas or make them inaccessible to bears. This is particularly true of open areas used during early spring since they tend to be small (< 0.5 ha). Residential development in or near large blueberry patches may bring bears into conflict with humans. Bears may continue to use the berry patch and may also start to forage around homes and businesses looking for edible refuse. Nuisance bear complaints may become frequent. Development on adjacent lands may result in the same nuisance bear effect since bears travel considerable distances to reach feeding areas.

Roads, buildings, and construction of other structures may destroy the function of a unique feeding area. If significant food resources remain distributed around the structures, bears will continue to come to the site. If the structures are not inhabited when bears are using the unique feeding area, the effects may be minor. Any time humans and bears are brought into contact, bears will  be deterred from returning to the site. If this occurs, a significant food source for a local bear population will have been lost resulting in the reduction of carrying capacity for the area. A reduced food supply will force bears to seek alternate food sources, which again may result in conflicts with humans.

Forest clearing and excavation can result in the permanent loss of unique feeding areas like forest openings, blueberry patches, and oak and beech stands.

Mitigation

The main problem associated with development is the human/bear conflict which often results. Although a development proposal may indicate that it impacts very little of the unique feeding area, or that it is located only on adjacent lands, some nuisance bear problems may occur. The magnitude of the problem will depend on the density of bears in the area, the attractiveness of the unique feeding area to bears, and the availability of other similar feeding sites. The greatest challenge facing mitigation attempts is the identification of important feeding areas and movement corridors linking them. Only when this is done can development be planned to avoid these areas.

Developments in or adjacent to unique bear feeding areas will have to have plans for management of human refuse. Garbage pails and waste transfer sites are spots that attract bears. Efficient garbage collection and storage is an important consideration in bear country. An education program to teach residents how to live with bears may be useful.

Alternate food sources may be created in some cases, by planting berries or mast trees, or by planting lure crops such as corn in an attempt to draw bears away from human habitations. This would have to be done well away from the development, as it may simply attract more bears to the area. Also, mast trees take several years to grow to the point where they are likely to produce mast.


Index #50 - Woodland/Forest/fisher and marten/Rare or Specialized Habitat/Maternal Dens
Index # 50

Habitat Type:	Woodland/Forest

Species Group:	fisher and marten

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat:	Maternal Dens

Habitat Function and Composition

Marten and fisher are both carnivores and members of the mustelid family. They frequent coniferous and mixedwood forests. Both species require large, unbroken blocks of suitable forest habitat to maintain viable populations. Fisher and marten use dens for resting and raising young. Dens provide protection from the elements and predators.

Martens den on or under the ground in rock piles, hollow logs, tree roots, or under the snow. Maternal dens are usually in cavities in dead and living trees or fallen logs.

Fisher make use of temporary dens located under logs, brush piles, or tree roots, in hollow trees or ground burrows or under snow. Maternal dens usually occur in tree cavities on or near the ground, but dens in rock ledges are also used.

Productive marten and fisher habitat requires the presence of large, unfragmented coniferous and mixedwood forests with a good supply of large standing trees providing cavities for nesting. Large trees act as the best sources of maternal den sites since they provide cavities large enough to raise young. Trees larger than 40 cm diameter at breast height are preferred. Any species of tree can act as a den site. Marten often use holes originally made by woodpeckers that have rotted out to provide the required cavity size. The marten is much more arboreal than the fisher, and may den higher up in trees, while fishers tend to den at the base of trees.

Potential Development Effects

Development which affects the integrity of the forest will have significant impacts on the use of the area as breeding habitat by marten and fisher. Excessive forest fragmentation may make the habitat unsuitable for marten and fisher.

Development activities which result in the removal of standing dead timber or reduce the structural complexity of the forest understory will reduce the number of maternal den sites available to these two species.

Development on adjacent lands may have an impact on the function of maternal den sites. If development on adjacent land results in an increase in human activity in the woodland used by marten and fisher for breeding, then den sites may take on even more significance for populations of these species.  Loss of quality den sites can affect the productivity and persistence of marten and fisher populations. Fisher have expanded their range further south in Ontario in recent years and have been implicated in killing of cats resulting in human/fisher conflicts in residential areas. Marten are quite sensitive to the presence of people and may avoid areas of human settlement, but fishers are much more adaptable to the presence of humans.

Tree removal, excavation, and other site alterations which result in the opening of the forest canopy, removal of standing dead timber, or simplification of the structure of the forest understory, may affect the breeding success of marten and fisher populations. Impacts on breeding present serious problems for marten and fisher populations. Impacts are greatest in areas where populations are already under stress owing to forest fragmentation and other aspects of habitat loss. Small, isolated populations are most sensitive to disturbance.

Both these species have large territories. The degree of impact may depend in part on how much suitable denning habitat is within their territory. In areas where there is a shortage of good den sites, potential impacts of development are much greater.

Mitigation

The effects of development on marten and fisher habitat can be reduced if provisions are made to retain large standing dead trees in areas of continuous coniferous and mixed forest cover. This may involve designation of some areas as natural hazard area to reduce the safety risks associated with unstable snags. Long-term consideration is required to ensure that a supply of maternal dens develop over time to replace snags which fall. The life of a maternal den tree could be extended using interventions to stabilize them.

Other mitigation methods which prevent the loss of downed woody debris and other natural features which increase the complexity of the forest understory will help to offset the loss of habitat area due to development. Increased complexity of the forest understory helps to increase small mammal populations (food supplies) and provide hiding cover which reduces mortality rates particularly on young marten and fisher.

Development should be planned so that large forested areas are not fragmented. Both of these species have large home ranges and require extensive blocks of habitat and good corridors linking areas of prime habitat.


Index #51 - Woodland/Forest/moose/Rare or Specialized Habitat/Mineral Lick
Index # 51

Habitat Type:	Woodland/Forest

Species Group:	moose

Significant Wildlife Habitat Category:	Rare or Specialized Habitat

Functional Habitat:	Mineral Lick

Habitat Function and Composition

In some places groundwater upwelling brings high concentrations of minerals to the surface creating pools or patches of wet soil rich in mineral content. The chemical composition of mineral licks varies greatly from site to site, but common elements include sodium, calcium, and magnesium.  Since not all upwellings contain high mineral concentrations, mineral licks occur infrequently across landscapes.

During spring, herbivores like moose (and white-tailed deer) consume plants which are much higher in potassium than sodium. This dietary imbalance results in flushing of sodium from the body. As a result, moose develop a considerable “thirst” for sodium in the spring. Consequently, moose frequently visit mineral licks in the spring to drink sodium-rich water or eat sodium-rich soil. These areas often attract large concentrations of animals.

Moose use mineral licks for a period of about 1.5 months beginning with the onset of the growing season. In June, moose use of mineral licks declines as most animals begin using aquatic feeding areas where they consume large quantities of sodium-rich aquatic plants.

For an upwelling or spring seep to function as a mineral lick for moose, it must provide relatively high concentrations of sodium in water or mud. Licks tend to be located in forest openings. The composition and structure of the surrounding forest varies greatly since it is the unique groundwater conditions which determine the location of the lick. Surrounding forest cover, and lack of human disturbance, are key features of mineral licks. If these conditions are met, then the lick will probably show a long history of seasonal use by moose. This can be recognized by trails radiating from the site, trampled soil and usually exposed rocks (a result of erosion at the site caused by trampling by moose).

Mineral licks rarely occur in areas of granitic bedrock except where the site is overlain by calcareous glacial till. They occur more frequently in areas of sedimentary and volcanic bedrock (another factor leading to their rarity).

Potential Development Effects

Development has a high potential for disruption of mineral lick functions. The effects can be manifested in several ways: disruption of hydrological function at the site; disturbance of moose using the lick; and/or complete destruction of the site.

If development activities within the area identified as significant wildlife habitat (the upwelling and surrounding forest cover) affect the flow of surface water or groundwater, they could easily destroy the mineral lick. Even relatively minor changes in flow rates could alter the chemistry of the lick reducing its quality and hence its usefulness to moose. The risks associated with disruption of surface flow extend into adjacent lands. For instance, development on adjacent lands could reduce infiltration and reduce or eliminate the volume of upwelling.

Development also has the potential to alter the water chemistry of upwellings through contamination of surface water or groundwater.

Moose are intolerant of human disturbance outside of areas where they are protected, such as provincial parks. Development within the forest surrounding the upwelling will greatly reduce the use of the mineral lick particularly if human activity is increased during the spring and early summer. Activity or construction of permanent buildings within sight of the upwelling will probably lead to the abandonment of the lick by moose. Development on adjacent land would have to be relatively minor with little increase in daily activity for it to have a benign effect on mineral lick use.

Site alterations such as erection of buildings or other structures, grading, filling, or excavation may disrupt the function of an upwelling as a mineral lick. The risks are associated with both changes to hydrological function of the site and human disturbance. Even minor changes to water flow may alter the chemistry of the lick rendering it unsuitable for moose. These kinds of site alterations present the same risks when conducted on adjacent lands.

Roads which are placed where moose must cross them to reach mineral licks present a considerable hazard to motorists. Significant moose mortality and potentially human injury and mortality may also result from collisions with vehicles.

Mitigation

Because mineral licks are uncommon features and have great attraction for moose, development should avoid these areas. Any proposed development should be no closer than 500 m. Also, roads should be planned to reduce the potential for moose/vehicle collisions.

Regardless of where development is proposed (i.e. the immediate area of the mineral lick, or adjacent lands) great care must be taken to ensure that surface water and groundwater flows and quality are not affected.

If development is planned for the area of the mineral lick, it should be planned so that increased human activity does not occur within sight of the upwelling. Natural vegetation should be left to conceal buildings, roads, etc. from the lick. Alternatively, trees and shrubs could be planted to create a barrier or screen.

Development which will increase human activity within the vicinity of the upwelling or on adjacent lands during spring and early summer should ensure that humans are not visible from the mineral lick. Also, noise associated with the human activities should be minimized at least during the season that moose are using the lick.


Index #52 - Woodland/Forest/moose/Seasonal Concentration Area/Late Winter Habitat
Index # 52

Habitat Type:	Woodland/Forest

Species Group:	moose

Significant Wildlife Habitat Category:	Seasonal Concentration Area

Functional Habitat:	Late Winter Habitat

Habitat Function and Composition

As winter progresses moose move to dense stands of mature conifers in response to deep snow conditions (this generally occurs during late February). For many moose, this movement simply results in a shift in the way they use habitat within their home range, which measures between 20 and 40 km2. This range shift results in moose using a restricted area of their home range measuring perhaps only 2 to 8 km2. For other moose, use of late winter habitat results in moving a considerable distance away from areas used during summer and autumn. As a result of these movements, moose distribution during late winter is closely allied to the distribution of mature coniferous cover. Any patch of suitable late winter habitat within moose range may be used during a given winter. Some patches may be used year after year, while others are used less frequently or perhaps not at all depending on the size of the moose population, snow depth, the distribution of predators, and the impact of human activity.

The coniferous cover available in late winter habitat reduces snow depth and the frequency of formation of crusts. By reducing snow depth, and moderating the formation of crusts, these areas convey several key survival advantages to moose. Moose are able to move more freely through the shallower snow beneath conifers. This saves them considerable energy and leads to increased chances of overwinter survival, and in the case of pregnant cows, increased survival of the offspring they are carrying. The less restrictive snow conditions in late winter habitat also allow moose to better evade predators. Coniferous cover also acts as a windbreak providing relief from wind chill, a further energy saving.

For an area to function as late winter habitat for moose it must be well supplied with coniferous trees more than 6 m tall. Stands should exceed about 4 ha and coniferous trees should form a canopy with closure of more than 60%. Moose will use stands composed of a variety of coniferous species but stands containing hemlock, balsam fir and white spruce provide superior snow interception qualities. The best late winter habitat also has some south-facing slopes and open areas where moose can move to on bright, sunny days to absorb the radiant energy.

The coniferous stand itself can be considered the late winter habitat. To function effectively as such, the stand must be surrounded by adjacent forested land with an understory well stocked with browse.

Potential Development Effects

Development in late winter habitat may ultimately force moose to abandon the area they have selected for use during late winter. This may be the only available site. This may come about through alteration of the composition and structure of the forest canopy or simply due to increased human activity in the area. Moose are intolerant of most forms of human disturbance, particularly if humans become a constant presence in the area (i.e. occupy the site for the duration of moose use). Cottages used during winter and resorts may be the greatest problem, particularly if winter recreation activities such as snowmobiling and cross-country skiing are associated with these facilities.

When displaced by development, moose are forced to find alternative late winter habitats. If these are in short supply, they may be forced to occupy less suitable sites. Even if other stands providing suitable winter cover are available, they will likely be occupied by other moose. This situation would lead to animals either having to share resources or compete for habitat. In either case, some or all of the moose will be receiving less than optimal supplies of critical late winter habitat. This results in an overall reduction in the winter carrying capacity (the number of moose it can sustain during an average winter) of the township or wildlife management unit.

Development planned for adjacent lands (in the case of moose, this will likely be woodlands) may not result in loss of function provided that the conifer stand is not disturbed either directly or indirectly by human activity (i.e. cross-country skiing or snowmobile trails).

Any site alteration which reduces the closure of the conifer stand below about 60% will result in a loss of function of the stand as late winter cover. Site alterations which have a lasting impact on the stand (i.e. building construction, road construction, golf course development, etc.) will result in a loss of function if they occur in the conifer stand itself. Road and trail construction on lands adjacent to the conifer stand will likely lead to a loss of habitat function if activities associated with these structures occur during late winter. Roads may also result in moose and potentially human mortality.

Mitigation

Important late winter moose habitat and associated feeding habitat should be identified early in the planning process. If it is determined that there is a limited amount of this habitat, then greater effort should be made to protect it from development. These areas can be very critical parts of moose habitat and as such should be identified as significant wildlife habitat and protected. Late winter habitat and feeding areas should not be separated by development or human activities.

It would be very difficult to mitigate the effects of any development proposed for the coniferous stand that makes up the late winter cover. Reduction of canopy closure to < 60% and/or conversion of the stand to a mixed or deciduous stand would destroy its function as late winter habitat owing to changes in stand composition and structure. Increased human activity in the stand during late winter would result in moose abandoning the site owing to their sensitivity to disturbance.

Attempts could be made to enlarge the stand through planting or forest cutting. This would have to be done many years in advance of the site alteration as only mature conifers provide the necessary cover for moose. The stand would have to be extended a considerable distance from the impact (i.e. > 1 km) if the stand were to retain its function as late winter habitat. Since moose are not tolerant of human activity, there is a low probability that this kind of mitigation strategy would actually retain the function of the coniferous stand as late winter cover.

Minor development impacts on forest land adjacent to the coniferous stand could occur without affecting the function of the coniferous stand as late winter habitat as long as site alterations do not remove a significant amount of the stand area and buildings are not within about 300 m of coniferous cover. Human activity on adjacent lands must not increase significantly during winter.

In case of cottage development, perhaps cottages could be clustered away from the important cover. This, however, may not be very attractive to potential cottagers.


Index #53 - Woodland/Forest/Wild Turkey/Seasonal Concentration Area/Winter Range
Index # 53

Habitat Type:	Woodland/Forest

Species Group:	Wild Turkey

Significant Wildlife Habitat Category: 	Seasonal Concentration Area

Functional Habitat:	Winter Range

Habitat Function and Composition

As winter approaches and snow accumulates, turkeys shift their activities to areas with coniferous stands and seeps. Since these features tend to be in limited supply, range shifts bring relatively large numbers of turkeys together in local areas functioning as winter range. Some turkeys may move several kilometres to winter range depending on the dispersion of conifers in the landscape. Areas may or may not be used consistently as winter range through time. Use seems to be dictated by location, annual food supply, and available coniferous cover rather than tradition. Winter severity may also be a factor in determining if an area is used as a winter concentration site. Areas that are used consistently among winters likely have stable, abundant, and  high quality food sources (i.e. corn fields, acorns) located nearby.

As snow accumulates, much of the turkey’s food supply (fruits, nuts, weed seeds, leftover crops, etc.) is buried (turkeys feed almost exclusively on the ground). To offset the reduction of food supply, turkeys restrict their movements and select mature coniferous trees as roost sites taking advantage of the thermal cover and concealment their branches provide. Turkeys seek refuge from winter storms in coniferous cover. Snow depths of 15 to 20 cm limit the ability of turkeys to walk, and when deep powdery snow conditions prevail (> 35 cm powder snow) all ground movement is prevented, forcing birds to roost until travel conditions improve. If ground travel is restricted for more than about two weeks, widespread turkey mortality is likely. Since conifers intercept snow, they effectively reduce ground accumulations. Therefore, snow depths under conifer cover are significantly lower than in deciduous or mixed forest stands. Turkeys are often able to travel and forage beneath conifer cover when they could not do so in adjacent deciduous or open habitats. Snow depths are also reduced in areas of seeps where percolating groundwater melts snow. These areas are prime feeding sites providing food in the form of foliage and invertebrates. These foods are in short supply during winter but are important sources of protein. Coniferous cover and seeps are two winter range habitat features which are key to overwinter survival of wild turkeys.

Turkeys will use a variety of coniferous species as roost trees. Hemlock stands appear to offer the best thermal protection and are often selected when winter weather is particularly severe; pines are also often used. Turkeys generally use the largest trees available, making stands of mature conifers particularly significant as winter cover. Coniferous stands used by turkeys are usually located in valleylands on the valley floor or on lower slopes. Primary roosts are located close to winter food supplies which, in many cases, may be agricultural fields where they scratch for seeds left behind after harvesting. They also feed extensively on acorns where they are available.

Any seep located within forest cover adds to the quality of winter range. Seeps located in open areas may also be used by turkeys provided they are not far from cover (i.e. < 100 m).  High quality seeps occur on slopes with southern aspects (greater potential for reduced snow depth and increased food availability due to exposure to sunlight).

Potential Development Effects

Development may significantly alter a site, reducing or eliminating its function as winter range for turkeys. Turkeys will stop using an area if coniferous cover is eliminated or the supply of mature conifers is reduced. Buildings constructed within coniferous cover will eliminate the function of the stand as winter range owing to site disturbance and loss of associated forest understory. Turkeys may abandon a winter range area if site alterations disrupt hydrological functions causing seeps to dry up or if additional feeding sites are not available nearby. Site alterations which isolate or leave seeps exposed will also reduce the attractiveness of the area as winter range. Since turkeys appear to make winter range selection decisions annually, site alterations can easily affect whether an area continues to be used as winter range. Loss of winter range function at the site level will result in the reduction of winter carrying capacity for turkeys across the landscape. The impact that this has on turkey populations in a township or county will depend on the availability of other sites which could function as suitable winter range. There is a large potential for reduction in Wild Turkey populations through cumulative impacts if there is relatively high pressure to develop in areas of mature coniferous cover associated with valleylands. Winter is the time of year that is most limiting to Wild Turkeys. Loss of cover will reduce the winter range carrying capacity.

Development on adjacent lands will have relatively minor impact on Wild Turkey winter range provided that groundwater flow is not affected causing changes in spring seep availability or water quality. Turkeys can become used to people and when weather conditions are harsh will often visit bird feeders. However, this is often a desperation measure when turkeys are faced with starvation. Even these fed birds need nearby coniferous cover for roosting. In the long term, increased mortality of birds (hunting or otherwise) which become used to people may offset the nutritional benefits they receive from being fed.

Lot clearing and excavation are two site alterations which may affect the function of woodlands as Wild Turkey winter habitat. Forest cutting which reduces the number and size of coniferous stands in an area will affect the winter carrying capacity of a region for turkeys. Forest cutting on adjacent lands may be benign and may increase winter food availability provided it is not associated with intensive building construction. Excavation, even on adjacent lands, may affect regional hydrology and therefore has the potential to disrupt the spring seep component of quality winter range. Building which increases human activity (and the activity of pets, particularly dogs) may affect the use of an area as winter range via disturbance. Wild Turkeys are usually intolerant of human disturbance within roosts and may abandon sites if disturbed frequently.

Mitigation

Mature coniferous stands and spring seeps are two features that should be identified early in the planning process. Conifers near a regular food source (oak stand or agricultural land) are of special importance. In some areas there may be a shortage of mature coniferous stands and/or spring seeps. The areas that do exist take on a greater importance and should be protected. Springs and seepage areas in woodlots are often valuable habitat for a number of species. These areas should be identified and protected from development. They often serve very important hydrological functions. Stands of large conifers can often be identified from aerial photographs. It is important that a good distribution of these sites be protected.

The effects of any development or site alteration on Wild Turkey winter habitat may be made less severe by directing the activity away from coniferous stands and spring seeps. Stands of oaks should also be maintained, as acorns are an important autumn and winter food.

Tree planting to extend the size of coniferous stands away from the development can be beneficial but must be viewed as long-term mitigation. Only mature conifers are useful as roost trees so it may be 40 to 60 years before established trees contribute to winter range function. In the interim, winter range function may be severely disrupted or totally eliminated depending on the extent of existing coniferous stand disruption and the sensitivity of turkeys to human disturbance.

Excavation and other development activities which affect groundwater and the hydrology of spring seeps may be difficult to mitigate. Even slight changes to the landscape and vegetation patterns can impact water flow patterns and quality.

Tree planting around a seep in an open area may make it more attractive to Wild Turkeys, as they prefer to have some cover. Tree planting around open seeps should not be undertaken if the tree cover has the potential to dry up the seep due to increased evapotranspiration.


Table 41-1
TABLE 41-1  GENERAL HABITAT REQUIREMENTS OF BIRD SPECIES VULNERABLE TO FOREST FRAGMENTATION

Species	Habitat Characteristics
Sharp-shinned Hawk	Nests almost exclusively in coniferous forests, seldom in mixedwood stands; preferred forests are very dense, with 80% or more canopy cover, are even-aged, and typically 25 to 50 years old; plantations are frequently used; nests in upland and lowland stands, but appears to prefer wetlands or areas near lakes or watercourses; nests are usually at the edges of forest; forests larger than 30 ha appear to be preferred
Cooper's Hawk	Nests mostly in deciduous forests, less frequently in mixedwoods; in western North America, it often nests in coniferous plantations and even in cities; in Ontario, it is usually associated with forests 50 ha in area or larger, but may occasionally use woodlots as small as 4 ha or even smaller; tends to nest in intermediate-aged and mature forests; prefers upland forests; tends to nest in forest interior
Northern Goshawk	Nests in mature deciduous, mixed, and coniferous forests, including plantations; inhabits closed-canopy forests with few shrubs or saplings in the understory; nests mostly in forests 100 ha in area or larger; nests in the interior
Red-shouldered Hawk [VULNERABLE]	Nests mostly in mature mixed and deciduous forests, occasionally in pine plantations; lowland forests are preferred, as amphibians comprise a large proportion of the diet; requires a closed canopy with a minimum of shrubs and saplings; appears to prefer forests larger than 100 ha, but occasionally nests in smaller stands; tends to nest in the interior
Broad-winged Hawk	Nests mostly in mature, dense mixed and deciduous forests, less frequently in coniferous stands and plantations; prefers lowland stands or forests that are close to swamps or open water; appears to prefer forests 100 ha in area or larger; nests are often at the edge of forests or near an opening
Ruffed Grouse	Nests in early successional forests; strongly associated with poplar and aspen stands but also occurs in other forest types; nests at the edge of forests or near small openings or disturbances in forests such as bush roads; relatively sedentary; hunted populations need forests of about 25 ha in order to maintain populations
Barred Owl	Nests in mature deciduous and mixedwood forests; needs large numbers of trees larger than 50 cm dbh; inhabits both upland and lowland forests; avoids edges and nests in the interior; needs very large forests 100 to 400 ha minimum size
Chuck-will's-widow	Nests primarily in mature, dry oak-pine forests; nesting may occur throughout the forest, but often near an opening or edge; appears to need forests larger than 100 ha in the province
Whip-poor-will	Nests in deciduous, mixed, and coniferous forests; prefers young and intermediate even-aged stands; nests at forests edges or near or in forest openings; in southern Ontario, associated with contiguous forests 100 ha or larger; may require 500 to 1000 ha to maintain a viable population
Yellow-bellied Sapsucker	Nests in deciduous and mixed upland and lowland forests; prefers intermediate-aged and mature stands; appears to need at least 30 ha of forest; nests in the interior of smaller woodlots and throughout larger ones
Hairy Woodpecker	Nests in deciduous and mixed forests, seldom in conifers; appears to have a slight preference for upland stands; appears to need about 10 ha of forest; nests throughout woodlots from edge to interior
Pileated Woodpecker	Nests in mixed and deciduous stands, occasionally in conifers; needs mature forest and trees at least 40 cm dbh for nesting and roosting; presence of mature poplars is important in much of its range; usually nests in interior but occasionally on edges or in open situations; occasionally nests in hydro poles with a large enough diameter; appears to need about 30 to 50 ha of forest, but may incorporate several smaller woodlots into its home range
Acadian Flycatcher [THREATENED]	Nests in mature deciduous woods, often maple-beech, but also red maple swamps; often nests in or near an opening in the interior, but may also nest near the edge; appears to need at least 30 ha of forest
Least Flycatcher	Nests in semi-open and closed immature to mature deciduous and mixed forests, rarely in coniferous forests; usually nests near the edge or at forest openings, less common in interior; appears to be associated with forests 30 ha or larger, although it often nests in small copses of woods or even orchards near forest
Red-breasted Nuthatch	Nests in mixed and coniferous stands, including plantations, rarely in deciduous stands; prefers intermediate to mature woods, and seems to prefer red and white pine; most nests are in the interior; appears to need at least 10 ha of forest
White-breasted Nuthatch	Nests mostly in mature deciduous forests, less often in mixedwood stands, rarely in conifers; nests throughout the forest; appears to need a minimum of 10 ha
Brown Creeper	Nests in mature deciduous, mixed, and coniferous forests; appears to prefer swamps over upland habitat; tends to nest in the interior; appears to require a minimum of about 30 ha
Winter Wren	Nests mostly in coniferous and mixed forests, rarely in deciduous forests; in deciduous forests, may be associated with American yew ground cover; prefers swamps; territories in upland forests are usually adjacent to wetlands; prefers mature forests with lots of fallen logs; nests in the interior in the south; appears to need about 30 ha of forest
Golden-crowned Kinglet	Nests in dense, mature, coniferous stands, including plantations; tends to nest in the interior and appears to need about 30 ha of forest
Blue-gray Gnatcatcher	Nests in mature deciduous and mixed forests including swamps and upland stands; tends to nest in the interior, but may also nest at edges or even in relatively open habitats; appears to need about 30 ha of forest
Veery	Nests in deciduous and mixed swamps, seldom in coniferous swamps; may also nest in wet, shrubby fields and alder thicket swamps; nests throughout the forest and appears to need about 10 ha of forest
Hermit Thrush	Nests in coniferous, mixed, and (less frequently) deciduous forests; nests throughout the forest; appears to require 100 ha of forest in the south
Wood Thrush	Nests in upland deciduous and mixed forests, seldom in natural coniferous stands or plantations; nests throughout the forest; appears to need at least 4 ha of forest
Blue-headed Vireo	Nests in coniferous and mixed stands, rarely in deciduous forest; tends to nest in the interior, but may also nest at edges; appears to be restricted to forests 100 ha or larger in the south
Yellow-throated Vireo	Nests in deciduous and mixed stands; nests throughout the forest and may also nest in fairly open situations; appears to be associated with forests 30 ha or larger
Northern Parula	Nests in mature deciduous and mixed forests; requires Usnea lichen for nest material in most cases; tends to nest in interior, but may nest at edges; in the south, probably requires 100 ha of forest; presence of Usnea may be more important than location within the forest
Magnolia Warbler	Nests in mixed and coniferous forests, rarely in deciduous stands; tends to inhabit young and intermediate-aged stands; occurs in both upland and lowland areas; nests throughout the forest; appears to require at least 30 ha
Yellow-rumped Warbler	Nests in intermediate-aged and mature mixed and coniferous forests, rarely in deciduous stands; may also occasionally nest in young and intermediate-aged plantations; nests throughout the forest; appears to require about 30 ha of forest
Black-throated Green Warbler	Nests most often in coniferous forests, less often in mixed forests, rarely in deciduous stands; nests throughout the forest; appears to require about 30 ha of forest
Blackburnian Warbler	Nests in coniferous and mixed woods as well as spruce-tamarack bogs; nests throughout the forest; in the south, appears to require about 50 ha of forest
Pine Warbler	Nests mostly in mature white or red pines but other conifers are occasionally used; nests throughout the forest; appears to require about 30 ha of forest, although there are records of it nesting in isolated pine trees
Cerulean Warbler [VULNERABLE]	Nests in intermediate-aged and mature deciduous stands, less frequently mixed stands; tends to nest in the interior; appears to require 100 ha or more of contiguous forest habitat
Black-and-white Warbler	Nests mostly in mixedwoods, but also in coniferous and deciduous forests; seems to prefer mature habitats; tends to nest in the interior in the south; appears to require about 100 ha of forest
American Redstart	Nests in deciduous and mixed forests, rarely coniferous forests; nests at edges or in forest clearings; may also nest in open habitat or very small forest fragments if they are near larger forests; probably needs about 30 ha of forest in the vicinity
Prothonotary Warbler [ENDANGERED]	Nests in mature deciduous swamps, usually above or at the edge of water; requires dead trees with suitable nesting cavities; appears to be associated with large forests of 100 ha or larger; tends to nest in open areas
Ovenbird	Nests in deciduous, mixed, and coniferous forests that are intermediate or mature in age; may use coniferous plantations where hardwoods are regenerating or coniferous stands adjacent to deciduous forest; prefers upland habitat; nests throughout the forest; requires about 20 ha of forest
Northern Waterthrush	Nests in mixed and deciduous swamps, occasionally in coniferous swamps; nests throughout the forest; appears to select forest 20 ha or larger in size, but occasionally nests in very small woodlots
Louisiana Waterthrush [VULNERABLE]	Nests in mature deciduous and mixed forests; swamps are preferred and there is often open water nearby; tends to nest in the interior and is usually associated with forests 100 ha or larger
Mourning Warbler	Nests mostly in deciduous and mixed forests, occasionally coniferous forests; usually nests at forest edge, either in forested habitat or adjacent shrubland; tends to be associated with forests 30 ha or larger
Hooded Warbler [THREATENED]	Nests in mature upland or mixed upland forests or swamps; prefers forest openings where there is considerable sapling growth; nests throughout the forest, but may be associated with openings or disturbances within the interior; appears to require at least 30 ha of forest, perhaps 50 to 100
Canada Warbler	Nests in upland and lowland mixed, coniferous, and deciduous forests; appears to prefer extensive cedar swamps; may also nest in shrubby areas; may nest throughout the forest with a tendency to be in the interior in the south; probably requires about 30 ha of forest
Scarlet Tanager	Nests in deciduous and mixed forests, predominantly in deciduous woodlots; prefers intermediate-aged and mature stands; tends to nest near the interior but also nests on edges occasionally; appears to require at least 20 ha of forest
White-throated Sparrow	Nests in coniferous and mixed forests, and appears to have a preference for white cedar, although other coniferous species will be used; prefers swamps to upland forests, although they are occasionally used; nests on forest edge and throughout the forest; appears to require at least 10 ha of forest


Table 41-2
TABLE 41-2	SUSCEPTIBILITY TO INDIRECT IMPACTS OF DEVELOPMENT

Species	Avian Predators	Mammalian Predators	Parasitism	Human Disturbance
Sharp-shinned Hawk	very low	low	none	high
Cooper's Hawk	very low	low	none	moderate
Northern Goshawk	very low	low	none	moderate
Red-shouldered Hawk VULNER-ABLE	very low	low	none	high
Broad-winged Hawk	very low	low	none	moderate
Ruffed Grouse	low	high	none	high
Barred Owl	very low	low	none	low
Chuck-will's-widow	very low	high	none	low
Whip-poor-will	very low	high	none	low
Yellow-bellied Sapsucker	very low	none	none	low
Hairy Woodpecker	very low	none	none	low
Pileated Woodpecker	very low	none	none	low
Acadian Flycatcher THREATEN-ED	high	moderate	moderate	low
Least Flycatcher	moderate	moderate	low	low
Red-breasted Nuthatch	very low	none	none	low
White-breasted Nuthatch	very low	none	very low	low
Brown Creeper	very low	very low	none	low
Winter Wren	very low	moderate	none	low
Golden-crowned Kinglet	very low	low	none	low
Blue-gray Gnatcatcher	moderate	low	moderate	low
Veery	high	high	moderate	low
Hermit Thrush	moderate	high	low	low
Wood Thrush	high	high	moderate	low
Blue-headed Vireo	high	very low	low	low
Yellow-throated Vireo	high	low	high	low
Northern Parula	moderate	very low	low	low
Magnolia Warbler	moderate	low	low	low
Yellow-rumped Warbler	moderate	low	moderate	low
Black-throated Green Warbler	high	low	moderate	low
Blackburnian Warbler	high	very low	moderate	low
Pine Warbler	moderate	very low	high	low
Cerulean Warbler VULNER-ABLE	moderate	very low	moderate	low
Black-and-white Warbler	low	high	moderate	low
American Redstart	high	moderate	moderate	low
Prothonotary Warbler ENDANGERED	moderate	moderate	high	low
Ovenbird	low	high	low	low
Northern Waterthrush	low	high	low	low
Louisiana Waterthrush VULNER-ABLE	low	high	moderate	low
Mourning Warbler	high	high	low	low
Hooded Warbler THREATEN-ED	high	high	high	low
Canada Warbler	moderate	high	moderate	low
Scarlet Tanager	moderate	moderate	moderate	low
White-throated Sparrow	moderate	high	moderate	low


Introduction
Significant Wildlife Habitat:  Decision Support System

Introduction

The following information is provided as a means of verifying predictions made by proponents regarding the impact of proposed development on significant wildlife habitat. The Natural Heritage Policy states that development can occur in and adjacent to areas identified as significant wildlife habitat provided that it has been demonstrated that there will be no negative impact on the natural features and ecological functions of the area. The Decision Support System is intended to be used by planners as a guide to help them understand the functions of the habitat, potential impacts, and possibilities for mitigation. Planning authorities may request natural heritage studies if the proposed development occurs in or adjacent to areas that have been designated as significant wildlife habitat (see Significant Wildlife Habitat Technical Guide, OMNR, Southcentral Science Section, 2000). Significant wildlife habitat includes: seasonal concentration areas; rare vegetation communities or specialized habitats for wildlife; movement corridors; and the habitat of species of conservation concern. The decision support system is used after the site has been identified as being a natural heritage feature.

The information contained in this decision support system outlines the habitat needs of species or groups requiring similar significant wildlife habitat features. The function of significant wildlife habitat is described for each species or group. For example, certain woodlands function as winter concentration areas for white-tailed deer. Deer migrate seasonally to these areas, and by doing so, they increase their chances of surviving the winter. Information is provided about the composition and structure of woodlands which allow them to function as winter concentration areas for deer. The decision support system also provides information regarding anticipated impacts of development on significant wildlife habitat and the functions of the habitat for wildlife populations. The impacts of development on significant wildlife habitat functions are summarized.  Additional information is provided on possible mitigation techniques.


Species Habitat Requirements
Descriptions of Species' Habitat Requirements

Groups of species, or guilds, are often considered together within a single index or habitat. It is important to do this so that the system does not become too complicated and unwieldy. Although grouping of species with similar habitat requirements or that use a certain habitat type is essential to streamlining the system, this causes some problems when attempting to generalize habitat requirements, potential impacts of development, and mitigation techniques. The habitat requirements of individual species within a guild may vary substantially. Within broad habitats or guilds of species, mitigation to protect one species may be detrimental to another. An attempt has been made to deal with this by providing descriptions of the pertinent habitat requirements of each species within guilds where there is a disparity in the habitat used by different species.

For each index, where more than one species is involved, we have attempted to provide insights to the habitat requirements of each species. For instance, if the guild is grassland birds, a list of all species that fit into this guild is provided. Then a table is presented that summarizes the key habitat requirements for each species. This provides proponents and reviewers with information on which of the species in the proposed development area may qualify under the significant wildlife habitat component of the PPS, and what conditions should be maintained if that species is to remain on site.

The tables of habitat requirements for individual species within a guild also help to identify which species are most sensitive to development pressures. For instance, if one of the species documented as being present typically requires a field that is 75 ha in area, it will be much more likely to be affected by a reduction in field size than a species that is content in fields as small as 10 ha. In most cases, if habitat is protected for the most sensitive species, all others will also be protected.

The species listed under each guild are intended to be all-inclusive. Therefore, in some areas of the province, many of the species would not be considered significant. Determination of which species are significant should be determined using the significant wildlife habitat identification guidelines prepared by OMNR in 2000. The significance of many species will vary across the province depending upon their normal geographic range and the availability of suitable habitat within this range. In other words, a species may be common in the main portion of its range where there is ample suitable habitat, but may be a significant species at the periphery of its range or where habitat has been reduced.

There are also some species that are at risk because of a certain characteristics of their life history, but that are extremely abundant in some areas. Prime examples are some of the colonially-nesting bird species such as Double-crested Cormorant and Ring-billed Gull. In some areas, these species may approach nuisance levels and municipalities may choose not to consider their habitat to be significant. In areas where they are not common, nesting areas may be significant wildlife habitat.

The significant wildlife habitat component of the PPS applies throughout the province. For the sake of completeness, we have included all species that fit within the guild. For those that occur only in areas that are unlikely to be affected by development, such as on the Hudson Bay Lowland, detailed habitat requirements are not presented.

We have provided the most up-to-date information on species' habitat requirements that we are aware of. However, the habitat needs of many species are poorly understood. In addition, much of the literature is from the United States, and species' preferences there may differ in Ontario. The reality is that species adapt over time to the general characteristics of the landscape in which they occur. Some of the bird species documented as requiring 100 ha or more in the northeastern states inhabit much smaller patches in Ontario and reproduce just as successfully. In southern Ontario, the Winter Wren is a forest-interior bird that seldom occurs near edge; on the Canadian Shield, it often occurs on lake and river shorelines in areas that would be avoided in the south; in the United Kingdom, it is the wren that is found in backyards.

One of the habitat components that is important to species' maintenance is minimum patch size. This also varies across the province depending on the amount of natural habitat within the general landscape. In an agricultural landscape that is over 30% forested, a species may inhabit patches as small as 10 ha, but the same species may require 30 to 50 ha in regions where forest cover is sparse. This emphasizes the importance of maintaining as much forest cover as possible within a planning area. When giving estimates of habitat size requirements, we have tried to give an average that might typically be inhabited in areas with about 15 to 20% forest cover. Therefore, if the study area has less forest cover, the species is likely to require larger forests; smaller areas may be suitable where there is a higher percentage of forest cover.

All of the habitat requirements that are presented in the indices should not be considered absolute. Not only is there insufficient information for some species, habitat requirements may vary geographically and according to the quality of the landscape. Possibly the most important variable is the fact that we are trying to characterize entire species. The reality is that each species is comprised of a population of individuals, and that some will select habitat conditions different from most individuals of the species. These individuals often are successful in what we would consider abnormal habitat for them. To put it into context, what we are presenting is the equivalent of summarizing the habitat requirements of humans under four or five headings. It can be done in a general sense, but there will always be exceptions. The information provided in the decision support system is based on what the literature defines as typical habitat.

The descriptions of habitat requirements will always be a work in progress. As new information comes to light, the information in the tables will be updated. Users of the decision support system are urged to inform us of information that could improve the tables.


Development Effects
Description of Development Effects

In this portion of the index, we have attempted to think of all potential effects that development may have on the significant wildlife habitat and species that are dealt with by the index. Each development will be unique to some extent, and there are undoubtedly potential impacts that we have not identified. Proponents and reviewers should ensure that additional potential effects of development are considered. These should also be identified to the Ministry of Natural Resources so that the Decision Support System can be updated.

The indices deal only with potential effects of development on significant wildlife habitat. When preparing an Impact Assessment, proponents will also have to identify potential impacts on other natural heritage features such as significant wetlands, significant Areas of Natural and Scientific Interest, significant woodlands, significant valleylands, significant portions of the habitat of threatened and endangered species, and fish habitat.

Some threatened and endangered wildlife species are dealt with in this Decision Support System. In these instances, we have tried to identify what constitutes the significant portions of their habitat. This information will continue to be updated as recovery plans are prepared for these species.

Under the Planning Act, development means consents, subdivisions, and industrial and commercial developments, or basically anything that involves an application under the Planning Act. In an earlier version of the Decision Support System, breaking the potential development into categories was considered. However, in many cases, there was little difference in potential effects, and it added substantially to the complexity of the system. Proponents and reviewers may be able to use the potential impacts identified in the indices as a checklist to determine if the proposed development will result in any of the effects identified in the system. The onus is on the proponent to demonstrate that negative impacts will not occur to significant wildlife habitat. If potential negative impacts are identified, then the proponent must demonstrate that these impacts can be mitigated.

An Impact Assessment should consider the ultimate end product of a development, and assume the worst-case scenarios. For instance, if a subdivision will be built over four phases, the potential impacts of the entire development should be addressed as opposed to dealing with each phase individually. If the proposal is for cottage lot development, it could be assumed that these will be converted into year-round residences. Occasionally, these types of developments are approved thinking that significant wildlife habitat, such as deer wintering areas, will not be affected because there will be no human use during the winter. This often results in an underestimation of the true impacts of a development. Also, all aspects of the development should be considered, including site preparation, construction, and the final use. Previous development may have already reduced the quality of significant wildlife habitat, and further development may have additional impacts or result in loss of functions that would not have occurred without the previous development.

For some of the guilds that include several species, a table has been presented indicating susceptibility of the various species to different impacts. For example, the sensitivity of species to human activity may vary greatly within certain guilds.


Mitigation Measures
Description of Mitigation Measures

The best mitigation is to avoid significant wildlife habitat. This, however, is not always possible. When significant wildlife habitat may be affected by development, the proponent must identify mitigation techniques that will reduce effects to acceptable levels.

For each of the potential impacts identified in a index, possible mitigation methods are suggested. Again, for guilds containing several species, a table presents species-specific mitigation measures.

Many proponents will identify innovative mitigation measures that we have not considered. These should be described to the Ministry of Natural Resources so that the system can be updated.


How it works
Here is how it works

This application, the Significant Wildlife Habitat Decision Support System is meant to accompany the Significant Wildlife Habitat Technical Guide.  It operates the same as any Windows Help File.  When first opening the Significant Wildlife Habitat Decision Support System, the ‘Contents’ tab will be selected.  Topics will be listed under 4 categories, which are displayed as books.  They are:

Introduction

How to Use the Significant Wildlife Habitat Decision Support System

Descriptions

Indices

All topics of the Significant Wildlife Habitat Decision Support System can be reached through the ‘Contents’ tab.  Alternatively, the user can click on the ‘Index’ tab and select from the listed keywords to find their topic of interest.

For example, a consultant's report “comes in” suggesting that an area of shoreline which is being considered for multi-lot cottage development is used as an aquatic feeding area by moose.  From the report, the following keywords are identified (in bold); Habitat Type {open water shoreline}, Species Group {moose}, Significant Wildlife Habitat {rare or specialized habitat}, Habitat Function/Name {aquatic feeding area} By entering any of these four keywords the user will either jump to the relevant Index, or be presented with a list of topics that match the search criteria.  From this list, the user can select the Index that best matches their situation.  In this situation Index #20 matches all four keywords and is the best match.

Another method of accessing the decision support system is to review the species listed in the proponent's biological inventory. The ‘Species Index’ topic can be found in the ‘Contents’ tab under Indices, or by typing the keyword ‘Species Index’ at the ‘Index’ tab.  The Species Index topic lists all of the species available in the Significant Wildlife Habitat Decision Support System.  Users can click on their species of interest to display relevant topics.  In this example, clicking on moose - Alces alces in the Species Index would direct the proponent and reviewer to Index #20. It would also indicate that moose are also dealt with in Index #21, Index #51, and Index #52. Using the species index is a good crosscheck to ensure that all important species and significant wildlife habitats are dealt with.

Once the user has arrived at Index # 20, they will find information regarding moose aquatic feeding areas. The function and composition of aquatic feeding areas is described first, followed by potential effects of development on moose aquatic feeding areas and procedures that may mitigate the effects of development on the significant wildlife habitat.

.


Terms and Concepts

Wildlife - includes all non-domestic living organisms, from mammals to plants to bacteria. This decision support system has focused on insects, amphibians, reptiles, birds, and mammals.

Wildlife Habitat - is “home”. It means areas where plants, animals and other organisms live, and find adequate amounts of food, water, shelter, and space needed to sustain their populations. Specific wildlife habitats of concern may include areas where species concentrate at a vulnerable point in their annual or life cycle; and areas which are important to migratory or non-migratory species.

Significant Wildlife Habitat - Determining what constitutes significant wildlife habitat will vary across the province because of differences in the distribution of wildlife species, and the amount, distribution and quality of the habitat that remains. For example, winter deer habitat may be considered highly important in jurisdictions having relatively few winter concentration areas (deer yards), but less important in others with many yards. Technical guidelines (Significant Wildlife Habitat Technical Guide -OMNR, Southern Region Science & Technology, 1998) have been developed to assist planning authorities to identify and evaluate significant wildlife habitats in their areas.

Significant wildlife habitat is identified and evaluated for individual species and/or groups of species in the following categories:

•	Seasonal Concentration Area (SCA) - areas where animals occur in relatively high densities at specific periods in their life cycle and/or in particular seasons. Impacts which occur at sites of seasonal concentration have the potential to affect wildlife populations well beyond the site level.

•	Rare or Specialized Habitat (RSH) - rare vegetation communities (prairies, alvars, savanna, etc.) or habitats which satisfy specific life requirements of animals (i.e mineral licks, aquatic feeding areas, etc.). Elimination of these rare or specialized habitats from the landscape reduces the quality of wildlife habitat. In some cases the loss of these features may result in the total loss of habitat function for the species of concern.

•	Movement Corridor (MC) - habitat which links two or more wildlife habitats that are critical to the maintenance of a population of a particular species. Many wildlife populations depend on the process of dispersal to move individuals among sub-populations scattered throughout the landscape. Movement of animals serves to prevent inbreeding which results in less variation in the genetic makeup of the population. Populations with low genetic diversity are less able to adapt to changing environmental conditions and hence are more prone to extinction. In addition, otherwise suitable yet unoccupied habitat which is not linked to surrounding occupied habitat is likely to remain unoccupied because animals simply cannot reach the area.

•	Habitat of Species of Conservation Concern (HSCC) - includes significant portions of the habitat of species that are rare, substantially declining or have a high percentage of their global populations in Ontario. Since these species are living at low density, often in small localized areas, they are prone to extinction following relatively minor habitat disturbances. Many of the species in this group are intolerant of human activity. This presents a great challenge to mitigation.


Lookup Table
File Lookup Table

Habitat Type	SWH	Species Group	Function/Name	Index
cave/cliff	MC	Migrant birds	migration route	1
cave/cliff	SCA	Bats	hibernacula	2
cave/cliff	RSH	Cliff-nesting birds	nest sites	3
cave/cliff; woodland/forest	SCA	Reptiles	hibernacula	4
cave/cliff	SCA	Turkey vulture	summer roost	5
field/meadow	HSCC	grassland birds	breeding habitat	6
field/meadow	HSCC	insects	breeding habitat	7
field/meadow	RSH	raptors	hunting areas	8
field/meadow	SCA	amphibians	summer habitat	9
field/meadow	SCA	raptors	winter roost	10
field/meadow	RSH	waterfowl	nesting habitat	11
field/meadow; prairie/alvar/ savannah	HSCC	colonially-nesting birds	breeding habitat	12
open water shoreline	HSCC	amphibians	preferred habitat	13
open water shoreline	HSCC	amphibians	preferred habitat	14
open water shoreline; prairie/alvar/ savannah	HSCC	insects	preferred habitat	15
open water shoreline; woodland/forest	HSCC	reptile (skink)	preferred habitat	16
open water shoreline; prairie/alvar/ savannah	HSCC	reptiles	preferred habitat	17
open water shoreline	HSCC	spiny softshell turtle	preferred habitat	18
open water shoreline	RSH	mink and otter	feeding/denning sites	19
open water shoreline; wetlands	RSH	moose	aquatic feeding area	20
open water shoreline	RSH	moose	calving sites	21
open water shoreline; wetlands	RSH	raptors	nesting habitat	22
open water shoreline	RSH	reptiles	nesting habitat	23
open water shoreline	SCA	colonially- nesting birds	nesting areas	24
open water shoreline	SCA	migrant birds	migration route	25
open water shoreline	SCA	raptors	winter roost	26
open water shoreline	SCA	shorebirds	migration stopover areas	27
open water shoreline; woodland/forest	SCA	white-tailed deer	deer yard	28
open water shoreline	SCA	migrant butterflies	migratory stopover areas	29
prairie/alvar/savannah	HSCC	insects	preferred habitat	30
prairie/alvar/ savannah	HSCC	grassland birds	preferred habitat	31
wetlands; open water shoreline	SCA	waterfowl	moulting areas	32
wetlands	HSCC	spotted turtle	preferred habitat	33
wetlands	HSCC	eastern massasauga	hibernacula	34
wetlands	HSCC	marsh birds	breeding habitat	35
wetlands	SCA	colonially- nesting birds	nesting habitat	36
wetlands	SCA	waterfowl	staging areas	37
woodland/forest	SCA	colonially-nesting birds	breeding habitat	38
woodland/forest	HSCC	Kirtland’s warbler	preferred habitat	39
woodland/forest	SCA	amphibians	breeding ponds	40
woodland/forest	HSCC	forest-interior birds	breeding habitat	41
woodland/forest	HSCC	insects	preferred habitat	42
woodland/forest	HSCC	reptiles	preferred habitat	43
woodland/forest	HSCC	southern flying squirrel	nesting habitat	44
woodland/forest	HSCC	woodland raptors	breeding habitat	45
woodland/forest	MC	amphibians	woodland corridor	46
woodland/forest	HSCC	wood turtle	preferred habitat	47
woodland/forest	MC	white-tailed deer	migration trail	48
woodland/forest	RSH	black bear	unique feeding area	49
woodland/forest	RSH	marten and fisher	maternal dens	50
woodland/forest	RSH	moose	mineral lick	51
woodland/forest	SCA	moose	late winter habitat	52
woodland/forest	SCA	wild turkey	winter range	53


Landscape Approach
Using a Landscape Ecology Approach

Proponents and reviewers of Impact Assessments should always try to put the development proposal and its impacts into a landscape perspective. All too often, proponents simply state that there is abundant suitable habitat in the area and that wildlife will move to these areas. If this is used as rationale that the development will have no negative impacts, the proponent must be able to demonstrate where other suitable habitat is, that wildlife will actually have access to it, and that the other areas are not at carrying capacity. In most cases, other similar habitat will be at carrying capacity. The reality is that, if two pairs of a bird species breed in a habitat that will be removed by development, there will likely to be two fewer pairs of that species nesting in the province in future. It is the decision of the planning authority to determine if the loss of two pairs is acceptable, or the onus of the proponent to demonstrate that there actually will not be a loss.

As part of a landscape ecology perspective, thresholds should be considered. Will the development reduce the amount of forest cover in the municipality below a threshold that will result in the disappearance of certain wildlife species?  Is the habitat that will be affected one that is in short supply in the municipality, even though the habitat may be provincially common or even abundant?  Will the loss of the habitat result in the loss of a species from the municipality, even though the species may be common elsewhere?  Is the area a stepping stone for wildlife species travelling across the landscape?

Significant wildlife habitat must not be considered in isolation from other natural heritage features. For example, a forested valley with a watercourse running through it could contain several natural heritage features. A potential example is depicted at the end of the introduction. The planning authority could designate the valley as a significant valleyland and significant woodland. The watercourse would probably be fish habitat. Within the valley, there could be several sites that would qualify as significant wildlife habitat.

It is important to consider that an area will frequently function in more than one way as significant wildlife habitat. The interactions among these habitats and significant features must be considered in an Impact Assessment.


Difficult-to-Detect Species

Several of the significant species are very secretive or nocturnal. Even a very thorough inventory may fail to reveal the presence of some species. This factor often contributes to their vulnerability and scarcity. Their habitat may often be destroyed simply because no-one was aware that they occurred in the area.

The following species and groups of species that are dealt with in the Decision Support System are often overlooked during a standard inventory: salamanders, all snakes, rails, owls, bats, and southern flying squirrel. Among these, the species most at risk of not being detected are the bats, flying squirrels, and snakes. For salamanders, larvae can be collected from breeding ponds with a net, and this is probably the most efficient technique of confirming salamander species presence plus their active breeding ponds at the same time. Rails and owls usually respond readily to tape recordings of their calls, so it just takes a little more effort to inventory them. Bat detectors work to a point, but the frequency of the echolocation calls of many of the species overlap so that exact species cannot always be determined.

Some ideas for surveying the presence of southern flying squirrels were presented in the index for that species.

During the planning process, this is where identifying large parcels of land is beneficial and increases the likelihood of protecting these species.

It is recommended that planners prepare a list of significant wildlife species that are difficult to detect and that could potentially occur within their jurisdiction. This could be accomplished by looking at general range maps, or by contacting the Natural Heritage Information Centre to see if there had been any nearby occurrences. Then, when development is proposed within suitable habitat for one of the secretive species of concern, the Impact Assessment should be either prepared assuming that the species is present or a detailed enough inventory should be undertaken to demonstrate its presence or absence.


Acknowledgments

The primary contributors to the decision support system were Kerry Coleman (OMNR), Al Sandilands (Biological Consultant) and Tim Haxton (OMNR). Mike Dunkley (OMNR) developed the application to support the document. A number of people helped to develop the concept of a decision support system and provided the needed information. We are grateful to B. Law and S. Christilaw for their perspectives on the utility of this system to planners and future directions for development. Information sheets were reviewed by R. Brooks, M. McLaren, and M. Oldham -comments received were extremely helpful and much appreciated. Species habitat matrix data were provided in draft form by T. Bellhouse, D. Magee, and B. Naylor - this information helped considerably. We thank T. Broadfoot for reviewing and suggesting many improvements to an earlier version of this document. Jim Broadfoot of Broadfoot Consulting prepared the first version of the decision support system. His work formed the basis for this version. Finally, we are indebted to naturalists everywhere for their vigilance, keen eyes for detail, and willingness to share information.


Species Index

Insects

checkered skipper - Pyrgus communis

checkered white - Pontia protodice

fiery skipper - Hylephila phyleus

frosted elfin - Incisalia irus

Karner blue - Lycaeides melissa samuelis

little sulphur - Eurema lisa

monarch - Danaus plexippus

painted lady - Vanessa cardui

pipe vine swallowtail - Battus philenor

snout butterfly - Libytheana carinenta

the buckeye - Junonia coenia

variegated fritillary - Euptoieta claudia

West Virginia white - Artogeia (Pieris) virginiensis

Amphibians

American toad - Bufo americanus

blue-spotted salamander - Ambystoma laterale

bullfrog - Rana catesbeiana

chorus frog - Pseudacris triseriata

Fowler’s toad - Bufo woodhousii fowleri

gray treefrog - Hyla versicolor

green frog - Rana clamitans

Jefferson salamander - Ambystoma jeffersonianum

leopard frog - Rana pipiens

mole salamanders - Ambystoma spp.

pickerel frog - Rana palustris

red-spotted newt - Notophthalmus viridescens

smallmouth salamander - Ambystoma texanum

spotted salamander - Ambystoma maculatum

spring peeper - Hyla crucifer

wood frog - Rana sylvatica

Reptiles

black rat snake - Elaphe obsoleta obsoleta

blue racer - Coluber constrictior foxii

brown snake - Storeria dekayi

eastern garter snake - Thamnophis sirtalis sirtalis

eastern hognose snake - Heterodon platirhinos

eastern massasauga - Sistrurus catenatus catenatus

eastern spiny softshell - Apalone spinifera spinifera

five-lined skink - Eumeces fasciatus

milk snake - Lampropeltis triangulatum

northern ring-necked snake - Diadophis punctatus edwardsi

redbelly snake - Storeria occipitomaculata

red-sided garter snake - Thamnophis sirtalis parietalis

smooth green snake - Opheodrys vernalis

spotted turtle - Clemmys guttata

timber rattlesnake - Crotalus horridus

turtles

wood turtle - Clemmys insculpta

Birds

Acadian Flycatcher - Empidonax virescens

American Bittern - Botaurus lentiginosus

American Black Duck - Anas rubripes

American Coot - Fulica americana

American Golden-Plover - Pluvialis dominica

American Kestrel  - Falco sparverius

American Redstart - Setophaga ruticilla

American White Pelican - Pelecanus erythrorhychos

American Wigeon - Anas americana

Arctic Tern - Sterna paradisaea

Bald Eagle - Haliaeetus leucocephalus

Barn Owl - Tyto alba

Barred Owl - Strix varia

Black-and-white Warbler - Mniotilta varia

Black Duck - Anas rubripes

Black Tern - Chlidonias niger

Black-bellied Plover - Pluvialis squatarola

Blackburnian Warbler - Dendroica fusca

Black-crowned Night-Heron - Nycticorax nycticorax

Black-throated Blue Warbler - Dendroica caerulescens

Black-throated Green Warbler - Dendroica virens

Blue-gray Gnatcatcher - Polioptila caerulea

Blue-headed Vireo - Vireo solitarius

Blue-winged Teal - Anas discors

Boreal Owl - Aegiolus funereus

Brewer's Blackbird - Euphagus cyanocephalus

Broad-winged Hawk - Buteo platypterus

Brown Creeper - Certhia americana

Bufflehead - Bucephala albeola

Canada Goose - Branta canadensis

Canada Warbler - Wilsonia canadensis

Canvasback - Aythya valisneria

Caspian Tern - Sterna caspia

Cerulean Warbler - Dendroica cerulea

Chuck-will’s-widow - Caprimulgus carolinensis

Common Goldeneye - Bucephala clangula

Common Moorhen - Gallinula chloropus

Common Raven - Corvus corax

Common Tern - Sterna hirundo

Cooper’s Hawk - Accipiter cooperii

Dickcissel - Spiza americana

Double-crested Cormorant - Phalacrocorax auritus

Dunlin - Calidris alpina

Eared Grebe - Podiceps nigricollis

Eastern Screech-Owl - Otus asio

Forster's Tern - Sterna forsteri

Gadwall - Anas strepera

Golden-crowned Kinglet - Regulus satrapa

Grasshopper Sparrow – Ammodramus savannarum

Great Blue Heron - Ardea herodias

Great Egret - Ardea alba

Great Horned Owl - Bubo virginianus

Greater Scaup - Aythya marila

Greater Yellowlegs - Tringa melanoleuca

Green Heron - Butorides virescens

Green-winged Teal - Anus crecca

Hairy Woodpecker - Picoides villosus

Henslow’s Sparrow - Ammodramus henslowii

Hermit Thrush - Catharus guttatus

Herring Gull - Larus argentatus

Hooded Merganser - Lophodytes cucullatus

Hooded Warbler - Wilsonia citrina

King Rail - Rallus elegans

Kirtland’s Warbler - Dendroica kirtlandii

Lark Sparrow - Chondestes grammacus

Least Bittern - Ixobrychus exilis

Least Flycatcher - Empidonax minimus

Least Sandpiper - Calidris minutilla

Lesser Scaup - Aythya affinis

Lesser Yellowlegs - Tringa flavipes

Lincoln's Sparrow - Melospiza lincolnii

Little Gull - Larus minutus

Loggerhead Shrike - Lanius ludovicianus

Long-eared Owl - Asio otus

Louisiana Waterthrush - Seiurus motacilla

Magnolia Warbler - Dendroica magnolia -

Mallard - Anas platyrhynchos

Marsh Wren - Cistothorus palustris

Merlin - Falco columbarius

Migrant birds

Mourning Warbler - Opororonis philadelphia

Northern Bobwhite - Colinus virginianus

Northern Goshawk - Accipiter gentilis

Northern Harrier - Circus cyaneus

Northern Parula - Parula americana

Northern Pintail - Anas acuta

Northern Saw-whet Owl - Aegolius acadicus

Northern Shoveler - Anas clypeatus

Northern Waterthrush - Seiurus novaboracensis

Osprey - Pandion haliaetus

Ovenbird - Seiurus aurocapilus

Peregrine Falcon - Falco peregrinus

Pied-billed Grebe - Podilymbus podiceps

Pileated Woodpecker - Dryocopus pileatus

Pine Warbler - Dendroica pinus

Prairie Warbler - Dendroica discolor

Prothonotary Warbler - Protonotaria citrea

Red-breasted Nuthatch - Sitta canadensis

Redhead - Aythya americana

Red-headed Woodpecker - Melanerpes erythrocephalus

Red-necked Grebe - Podiceps grisegena

Red-shouldered Hawk - Buteo lineatus

Red-tailed Hawk - Buteo jamaicensis

Ring-billed Gull - Larus delawarensis

Ring-necked Duck - Aythya affinis

Ross's Goose - Chen rossii

Rough-legged Hawk - Buteo lagopus

Ruddy Duck - Oxjura jamaicensis

Ruddy Turnstone - Arenaria interpres

Ruffed Grouse - Bonasa umbellus

Sanderling - Calidris alba

Sandhill Crane - Grus canadensis

Scarlet Tanager - Piranga olivacea

Sedge Wren - Cistothorus platensis

Semipalmated Plover - Charadrius semipalmatus

Semipalmated Sandpiper - Calidris pusilla

Sharp-shinned Hawk - Accipiter striatus

Sharp-tailed Grouse - Tympanuchus phasianellus

Shorebirds

Short-billed Dowitcher - Limodromus griseus

 Short-eared Owl - Asio flammeus

Snow Goose - Chen caerulescens

Snowy Egret - Egretta thula

Snowy Owl - Nyctea scandiaca

Sora - Porzana carolina

Tundra Swan - Cygnus columbianus

Turkey Vulture - Cathartes aura

Upland Sandpiper - Bartramia longicauda

Veery - Catharus fuscescens

Virginia Rail - Rallus limicola

Whip-poor-will - Caprimulgus vociferus

White-breasted Nuthatch - Sitta carolinensis

White-rumped Sandpiper - Calidris fuscicollis

White-throated Sparrow - Zonotrichia albicollis

Wild Turkey - Meleagris gallopavo

Wilson's Phalarope - Phalaropus tricolor

Winter Wren - Troglodytes troglodytes

Wood Duck - Aix sponsa

Wood Thrush - Hylocichla mustelina

Yellow-breasted Chat - Icteria virens

Yellow-bellied Sapsucker - Sphyrapicus varius

Yellow-headed Blackbird - Xanthocephalus xanthocephalus

Yellow Rail - Coturnicops noveboracensis

Yellow-rumped Warbler - Dendroica coronata

Yellow-throated Vireo - Vireo flavifrons

Mammals

big brown bat - Eptesicus fuscus

black bear - Ursus americanus

eastern pipistrelle - Pipistrellus subflavus

eastern small-footed bat - Myotis leibii

fisher - Martes pennanti

little brown myotis - Myotis lucifuga

marten - Martes americana

mink - Mustela vison

moose - Alces alces

northern long-eared bat - Myotis septentrionalis

river otter - Lontra canadensis

silver-haired bat - Lasionycteris noctivagans

southern flying squirrel - Glaucomys volans

white-tailed deer - Odocoileus virginianus


Seasonal Concentration Area
Seasonal Concentration Area (SCA) - areas where animals occur in relatively high densities at specific periods in their life cycle and/or in particular seasons. Impacts which occur at sites of seasonal concentration have the potential to affect wildlife populations well beyond the site level.


Rare or Specialized Habitat
Rare or Specialized Habitat (RSH) - rare vegetation communities (prairies, alvars, savanna, etc.) or habitats which satisfy specific life requirements of animals (i.e mineral licks, aquatic feeding areas, etc.). Elimination of these rare or specialized habitats from the landscape reduces the quality of wildlife habitat. In some cases the loss of these features may result in the total loss of habitat function for the species of concern.


Movement Corridor
Movement Corridor (MC) - habitat which links two or more wildlife habitats that are critical to the maintenance of a population of a particular species. Many wildlife populations depend on the process of dispersal to move individuals among sub-populations scattered throughout the landscape. Movement of animals serves to prevent inbreeding which results in less variation in the genetic makeup of the population. Populations with low genetic diversity are less able to adapt to changing environmental conditions and hence are more prone to extinction. In addition, otherwise suitable yet unoccupied habitat which is not linked to surrounding occupied habitat is likely to remain unoccupied because animals simply cannot reach the area.


Habitat of Species of Conservation Concern
Habitat of Species of Conservation Concern (HSCC) - includes significant portions of the habitat of species that are rare, substantially declining or have a high percentage of their global populations in Ontario. Since these species are living at low density, often in small localized areas, they are prone to extinction following relatively minor habitat disturbances. Many of the species in this group are intolerant of human activity. This presents a great challenge to mitigation.