Northern Prairie Wildlife Research Center
STATUS: Uncommon to locally abundant.
HABITAT: Prefers cold, shallow, rapidly flowing mountain streams in forested regions, but also inhabits ponds and lakes, along rocky Arctic shores, and in tundra. Loafs in shallows, or on a rock or log in a stream or ashore. Winters on marine waters, usually 6 to 12 feet deep, in heavy surf along rocky coasts.
SPECIAL HABITAT REQUIREMENTS: Shallow, swift streams or rivers, or pothole glacial lakes.
NEST: Nests on the ground on an island, in a recess in a stream bank, under bushes or trees, or occasionally in a hollow tree or a cavity among rocks. Usually nests within 6 feet (but sometimes up to 60 feet) from water, with overhead shelter.
FOOD: A proficient diver, seems to prefer to feed in rough waters broken by rocks and surf. Mostly (98 percent) consumes crustaceans and mollusks. Also eats stone flies and other insects, fishes, and echinoderms.
REFERENCES: Bellrose 1976, Cottam 1939, Johnsgard 1975b, Palmer 1976b, Terres 1980.