Northern Prairie Wildlife Research Center
HABITAT: Prefers to breed on small islands or islets with low, prostrate woody vegetation or other natural features to cover the nest, and with open shores, gravel bars, or rocks to provide roosting and preening areas for drakes and young. Although it prefers inland waters, it may be found along the coasts on shores and on marine islets. Winters mainly in estuaries and sheltered bays, less frequently on inland freshwater.
SPECIAL HABITAT REQUIREMENTS: Rivers, ponds, and lakes with some overhead cover nearby for nesting.
NEST: Nests on the ground under low cover, generally within 33 feet of water, preferably on islands, but also on riverbanks and lakeshores, in marshes, on rocky islets, or in bank recesses. Nests may be under low conifer boughs; under or between boulders in shallow cavities; in tall grass, heather, or bracken; or under driftwood.
FOOD: Feeds primarily on fish caught during dives underwater. Also eats fish eggs, frogs, annelids, nymphs, caddis flies, amphipods, crabs, prawns, and mollusks.
REFERENCES: Bellrose 1976, Clapp et al. 1982, Johnsgard 1975b, Palmer 1976b.