A hydrogeomorphic inventory of coastal wetlands of the Manitoba Great Lakes: Lakes Winnipeg, Manitoba, and Winnipegosis

Abstract

We compiled an GIS-based inventory of coastal wetlands associated with the Manitoba Great Lakes—Lakes Winnipeg, Manitoba, and Winnipegosis—using a hydrogeomorphic classification system, orthophotography, satellite imagery, and digital habitat maps. The lakes have six times more wetlands per km of shoreline than the Laurentian Great Lakes: Lake Winnipeg has 1404km2 (0.8km2/km), Lake Manitoba has 564km2 (0.6km2/km), and Lake Winnipegosis has 742km2 (0.8km2/km). Riverine wetlands are the most common class on Lakes Winnipeg and Winnipegosis whereas barrier-protected wetlands are the most common class on Lake Manitoba. The totals for Lakes Winnipeg and Winnipegosis are greater by 548% and 273%, respectively, if Treed Muskeg habitat in the northern regions of the watersheds is included in the inventory, whereas the total for more southerly Lake Manitoba is greater by only 18%. Netley-Libau Marsh (222km2) on Lake Winnipeg and Delta Marsh (139km2) on Lake Manitoba are among the largest coastal wetlands on the North American continent. These baseline data can be used to identify ecologically important wetlands warranting further study or remediation.