Northern Prairie Wildlife Research Center
STATUS: Common to locally abundant.
HABITAT: Inhabits waters on open tundra or prairie with dense, low ground cover, preferably lakes larger than 110 acres, 3 to 12 feet deep and with dense submergent vegetation. Uses mixed tundra-taiga less frequently during nesting. In other seasons, can be found on marine and brackish waters along the coasts where the water is shallow over shellfish beds and the bottom is hard and sandy or gravelly, and occasionally on open freshwater.
SPECIAL HABITAT REQUIREMENTS: Lakes, ponds, and sluggish streams in northern prairie or tundra.
NEST: Nests in a hollow on the ground under dense, low spreading shrubs, preferably gooseberry, snowberry, rose, and raspberry, usually close to water, occasionally up to 450 feet and rarely a half mile away. May nest on islands, commonly uses old nest bowls, and in some instances may occupy active blue-winged teal or gadwall nests. Easily disturbed by human interference such as recreational boating on breeding lakes. Broods are reared in shallow, open water areas with submergent vegetation and some protection from wave action.
FOOD: Prefers to dive for shellfish in shallow water, usually less than 6 feet deep. Primarily eats animal foods (90 percent), mostly mollusks; also eats crabs, some fishes, aquatic insects, and sea lettuce.
REFERENCES: Brown and Brown 1981, Grosz and Yocom 1972, Palmer 1976b.