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Location Canada, Alberta
Central coordinates 115o 21.05' West  55o 27.66' North
IBA criteria A4i
Area 200,000 ha
Altitude 570 - 1,005m
Year of IBA assessment 2008

Bird Studies Canada/Nature Canada

Site description The massive Lesser Slave Lake in northcentral Alberta, is one of the largest lakes in the province. The town of Slave Lake is near the southeastern corner, and several small communities are located along the highway that runs along the south shore. The northern shore of this relatively shallow (20 m) lake is steeper and often rockier than the shallower southern shore, which contains various marsh communities. Sandy beaches and dunes are found at the eastern end of the lake. In Lesser Slave Lake Provincial Park (at the eastern end of the lake) and all around the lake, are hilly mixedwood forests of Trembling Aspen, Balsam Poplar, Balsam Fir, White Spruce and Black Spruce. Two Alberta subregions are represented here: Central Mixedwood and Lower Foothills. At the western end of the lake there is a rich delta leading into Buffalo Bay. Both marsh and swamp habitats are represented here.

Key Biodiversity This diverse area is host to over 200 species of birds, both landbirds and waterbirds. On Lesser Slave Lake itself, up to 3,500 swans occur in spring and fall. Since only a small portion (or none) of these are likely to be Trumpeter Swans, this number must represent between 1 and 2 % of the North American population of Tundra Swans. Depending on water levels, in some years, the swans can be found all along the south shore, while in other years they concentrate in certain locations, including Nine Mile Point and The Flats near Widewater. Other waterfowl are abundant during migration. In the delta at the west end of the lake, thousands of ducks congregate in the fall. Large numbers of Western Grebes, perhaps the largest in the province, nest in several places along the lakeshore there are records of 400 nests at Assineau Point, 200 nests at Driftpile Point and 50 nests at Giroux Bay.

During the breeding season, numerous other waterbird species are found here. Common Goldeneye, Mallard, Common Merganser, Bufflehead, Black Tern, Common Tern and Forsters Tern are just some of the regular breeders. The lake and its associated shoreline provide excellent habitat for breeding Bald Eagles and Ospreys. In August 1997, a survey of the lake and nearby shorelines produced an estimated 72 Bald Eagles.

The forests are rich in breeding forest birds. Some of the most abundant species are Lincolns Sparrow, Tennessee Warbler, Mourning Warbler, Rose-breasted Grosbeak, Yellow-bellied Sapsucker and Magnolia Warbler. In all, 20 species of breeding warblers have been recorded in Lesser Slave Lake Provincial Park. During migration, good concentrations of songbirds move between the eastern edge of the lake and Marten Mountain. Lesser Slave Lake Bird Observatory, established in 1994, has banded many neotropical migrants. The five most commonly banded species are American Redstart, Least Flycatcher, White-throated Sparrow, Alder Flycatcher, and Yellow-rumped Warbler.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Tundra Swan Cygnus columbianus passage  1985  3,500 individuals  A4i  Least Concern 
Western Grebe Aechmophorus occidentalis breeding  1975  650 nests  A4i  Least Concern 

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Hilliard's Bay Provincial Park 2,329 protected area contained by site 2,300  
Lesser Slave Lake Provincial Park 7,557 protected area contained by site 7,400  
Little Grassy Designation Not Known 563 protected area contained by site 570  


IUCN habitat Habitat detail Extent (% of site)
Forest Boreal coniferous forest; Boreal deciduous woods; Boreal mixed woods  -
Wetlands (inland)   -

Land use

Land-use Extent (% of site)
nature conservation and research minor
fisheries/aquaculture major
tourism/recreation major

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Lesser Slave Lake PP. Downloaded from on 27/10/2016

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