16-20" (41-51 cm). Male has glossy, dark green head with round white patch near base of bill; black back and tail; neck, breast, and sides white; white areas on wings and back visible in flight. Females' plumage is gray with darker gray wings and tail; brown head; bill dark with small pale yellow patch near tip.
Similar Species- Barrow's Goldeneye, female mergansers, male Bufflehead
Courting call of male is a double nasal quaa-quaak. Wings whistle in flight.
Breeds in Alaska, across parts of Canada, and south to northern Washington, central Montana, and across northern U.S. to Maine. Winters from southeastern Alaska to southern California, from Great Lakes to Gulf Coast, and from Newfoundland to Florida.
Found on ponds, lakes, rivers, and coastal bays, wintering primarily on bays and estuaries, less commonly on rivers and lakes. In Idaho, normally associated with water bodies near forests; prefers deep, open waters of large rivers, lakes, and reservoirs.
In inland areas during summer and fall, feeds on aquatic insects, crustaceans, and aquatic plants. Along coastal wintering grounds, feeds largely on crustaceans, mollusks, small fishes, and some plant material.
Builds nest in tree cavity near water. Dives under water to obtain food.
No references are available at this time.