Kaweenakumik Lake is located southwest of the town of Grand Rapids, in central Manitoba. A short distance to the west is Lake Winnipegosis and to the north is Cedar Lake, which is the storage basin for the Grand Rapids dam. This site is a freshwater lake with several islands of varying shapes located in its southern half. Some of the islands are small, rugged and rocky and largely devoid of any trees or shrubs, while others are large islands with little relief and substantial tree and shrub cover. The islands are important calving sites for Caribou.
The islands in Kaweenakumik Lake contain impressive colonies of colonially nesting birds. This is one of the largest congregations of breeding American White Pelicans in Canada. In the 1980s, an estimated 5,000 to 6,000 pairs bred here. One count from 1986 recorded 3105 nests, but it is not known if this is a full or partial count. Nonetheless the numbers of pelicans found here probably represent about 5% of the global population of this species.
At least 1,000 pairs of Common Terns (roughly 1% of the estimated North American population) were estimated to breed on the islands in the 1980s. A 1979 count recorded 400 pairs. Again, this may be a partial count, the tern numbers may have increased, or the first estimate is an overestimate.
Very large numbers of Ring-billed Gulls nest here; the numbers have variously been recorded as: 20,000 pairs in the 1980s, 4,000 nests in 1986, and 12,000 nests in 1979.
The Great Blue Herons nesting here exhibit unique nesting behaviour among Manitoba herons: rather than nesting high atop trees, several of these birds nest on the ground and the most nest about a metre above the ground in shrubs. Between 15 and 26 heron nests have been recorded. White-winged Scoters used to nest more commonly in the province, but the 8 pairs recorded at this site are a remnant population of this species in Manitoba. Other breeding species include: California Gull (30 nests in 1986), Double-crested Cormorant (250 nests in 1986), Herring Gull (7 nests in 1986), Western Grebe and American Avocet.
Parts of the site contain dense submergent aquatic vegetation and consequently support very large numbers of swans, geese and diving ducks during fall migration.
BirdLife International (2020) Important Bird Areas factsheet: Kaweenakumik Lake. Downloaded from http://www.birdlife.org on 14/07/2020.