Northern Prairie Wildlife Research Center
HABITAT: Inhabits permanent freshwater and alkaline prairie marshes having dense stands of cattails, bulrushes, whitetop, and reeds, and relatively stable water levels. Both large and small marshes are used for nesting, from potholes less than one acre to 1,200-acre sloughs. Commonly loafs and rests on water well out from shore. Prefers large bodies of shallow freshwater and brackish water, especially those with areas of aquatic plant growth, during migration. Winters on ice-free inland waters, or on sheltered shallow brackish or saltwater coastal waters.
SPECIAL HABITAT REQUIREMENTS: Open water areas close to dense emergent vegetation with muskrat channels or natural passageways to allow movement between the nest site and open water.
NEST: Usually nests over shallow water in emergent vegetation, on a floating mat of vegetation, or on a platform built up from the floor of the marsh. Occasionally nests on a muskrat house, on floating logs, or on an old coot nest. "Dump" nests are common in marshes with fluctuating water levels.
FOOD: Dives for food in waters 2 to 10 feet deep, and occasionally feeds on the water surface. Consumes about 72 percent plant foods, consisting of seeds, tubers, leaves, and algae. Also eats insects, snails, and some crustaceans.
REFERENCES: Bellrose 1976, Clapp et al. 1982, Cottam 1939, DeGraff et al. 1980, Johnsgard 1975b, Joyner 1969, Palmer 1976b, Siegfried 1976.