Full Site

Eastern Lake St. Clair (ON012)

Search

Eastern Lake St. Clair (ON012)

Southwestern Ontario, Ontario

Latitude 42.416°N
Longitude 82.552°W
Altitude 174 - 176m
Area 1,354.58km²

Site Description

Lake St.Clair, which forms part of the Great Lake system, is located in extreme southwestern Ontario to the north of the cities of Windsor and Detroit. The St. Clair River provides an inflow from Lake Huron to the north, and the Detroit River provides an outflow to Lake Erie to the south. The Eastern Lake St. Clair IBA encompasses the eastern shore, marshlands and agricultural fields from the Sydenham river at Wallaceburg to the mouth of the Thames River and the open waters of Lake St. Clair, south of the St.Clair River delta under Canadian jurisdiction. The large delta and the shallow nature of the lake result in extensive areas of marshland that is characterized by both submerged and emergent vegetation. Walpole Island, which is located within the St. Clair delta, contains some of the most significant tall grass prairie /oak savannah communities remaining in Canada.

Birds

Lake St. Clair is recognized as being one of the most significant staging areas for waterfowl in southern Ontario. During studies completed in the 1970s and early 1980s, it was estimated that peak totals of waterfowl were over 60,000 during spring migration, and over 150,000 during fall migration. The site was estimated to support 1,137,000 Canvasback and Redhead waterfowl-days, and as many as 5,123,000 dabbling duck waterfowl-days. (A waterfowl-day equals the number of ducks multiplied by the number of days present). The agricultural fields along the east shoreline also support large numbers of Black-bellied Plovers and American Golden Plovers during spring migration. As many as 5,000 Black-bellied Plovers have been reported, which could represent as much as 3.5% of the estimated North American population.

In addition to being significant as a staging area, the Lake St. Clair marshes also support significant populations of breeding birds. One of the largest breeding concentrations of Black Terns in Ontario is present, along with over 3.5 % of the estimated North American Forsters Tern population. The largest known Canadian population of King Rails (nationally endangered) has been recorded, along with significant numbers of Least Bitterns (nationally vulnerable).

The prairie and oak savannah communities of Walpole Island also support threatened bird species, with the largest self-sustaining concentration of Northern Bobwhite (nationally endangered) being present. There are also historic nesting records of Henslows Sparrows (nationally endangered), along with numerous other potential breeding records for nationally threatened species such as Acadian Flycatcher, Cerulean Warbler, Prothonotary Warbler, and Yellow-breasted Chat.

Conservation Issues

Although portions of this site are managed as protected areas (e.g., St. Clair and Bear Creek National Wildlife Areas, Tremblay Beach; Ruscom Shores Conservation Areas), there is still on-going loss and degradation of marsh habitat as a result of incremental land use change. A large proportion of the site is located within the Walpole Island First Nation Lands. Conservation of this site will require a lake-wide management system that is equitable for all users.

IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status
Tundra Swan
Number Year Season
1,500 - 10,8702016Winter
1,5002015Fall
2,4542015Winter
1,500 - 2,5002014Winter
3,000 - 8,5902014Fall
2,0002012Spring
3,8762012Winter
2,299 - 2,6852007Spring
2,004 - 6,5962007Winter
1,712 - 2,6142006Winter
1,8712005Winter
5,4302004Spring
5,4302004Winter
5,3311997Spring
4,300 - 5,3311997Winter
11,5001980Fall
135,0001980Spring
Canada Goose
Number Year Season
2,0002017Winter
2,5002016Fall
2,000 - 6,7892016Winter
2,0002015Fall
5,3682015Winter
2,5002014Fall
4,0502013Winter
1,800 - 12,2822012Winter
2,7322011Winter
4,4802010Winter
1,722 - 2,0002009Winter
2,2512008Winter
2,273 - 5,1202007Winter
1,834 - 2,7042007Spring
3,3032006Fall
3,5082006Winter
3,5662004Spring
3,5662004Winter
2,4632002Winter
9,0052001Winter
4,8352000Spring
4,8352000Winter
1,779 - 2,8101999Winter
6,3191998Spring
6,3191998Winter
6,6461997Spring
2,130 - 6,6461997Winter
3,5221996Winter
4,3101995Winter
7,7701994Winter
4,9341993Winter
3,1691992Winter
4,5131991Winter
2,5001990Winter
672,0001980Fall
378,0001980Spring
Red-breasted Merganser
Number Year Season
9,2382009Winter
16,2562006Winter
2,2562004Winter
2,0152000Winter
3,0961998Winter
4,0061997Winter
2,3061993Winter
4,5401992Winter
Canvasback
Number Year Season
12,0002015Spring
12,0002014Spring
16,9032012Winter
8,0002007Spring
25,8002007Winter
19,2152004Spring
19,2152004Winter
5,0002002Winter
Redhead
Number Year Season
5,0002016Spring
12,0022016Winter
15,2002007Winter
Rusty Blackbird
Number Year Season
30 - 1502016Fall
1002016Winter
25 - 2502015Fall
1502012Fall
292011Winter
282008Winter
46 - 1642007Winter
26 - 862006Winter
602006Fall
1872005Winter
34 - 382003Winter
382003Spring
302001Winter
1632000Winter
84 - 1451999Winter
1371998Winter
1131997Spring
1131997Winter
1371996Winter
301995Winter
881994Winter
941993Winter
1031992Winter
311991Winter
531990Winter
Black-bellied Plover
Number Year Season
3,9182007Spring
1,5001995Spring
1,5001994Spring
5,0001993Spring
Greater Scaup
Number Year Season
4,8162009Winter
9,5202003Winter
Herring Gull
Number Year Season
3,5002017Winter
3,0002016Winter
4,8262008Winter
2,8671996Winter
2,8701993Winter
2,9281990Winter
Little Gull
Number Year Season
21991Winter
Northern Bobwhite
Number Year Season
22014Spring
32012Summer
22006Spring
22003Summer
62002Summer
42002Spring
92001Summer
21999Summer
21997Spring
341995Summer
21995Spring
81992Spring
9 - 151991Winter
201990Winter
101990Summer
King Rail
Number Year Season
22014Summer
12012Fall
12012Summer
12007Spring
12006Spring
1 - 22005Summer
12005Spring
12005Other
1 - 22004Spring
12002Spring
12001Spring
11999Spring
11997Spring
321997Summer
11994Spring
Least Bittern
Number Year Season
751998Summer
131997Summer
Acadian Flycatcher
Number Year Season
21986Summer
Henslow's Sparrow
Number Year Season
12003Summer
21986Summer
Prothonotary Warbler
Number Year Season
12016Summer
12004Spring
11998Summer
21986Summer
Yellow-breasted Chat
Number Year Season
12013Summer
12004Summer
11996Spring
11995Spring
21986Summer
Barn Owl
Number Year Season
12008Winter
12007Winter
12006Winter
12003Spring
Kirtland's Warbler
Number Year Season
12005Spring
11996Spring
Waterbirds
Number Year Season
7,050,5001980Fall
1,580,0001980Spring
Bonaparte's Gull
Number Year Season
3,7292003Winter
3,3561996Winter
3,8491994Winter
American Black Duck
Number Year Season
5,3702007Winter
Ring-billed Gull
Number Year Season
22,1772001Winter
15,9421999Winter
20,1231993Winter
Chimney Swift
Number Year Season
252016Summer