Greater Scaup

General Description

The Lesser Scaup is one of the most abundant diving ducks in the Northwest. Male Lesser Scaups have white flanks, black rumps and breasts, and lined gray backs. They have purplish-black, iridescent heads and yellow eyes. Their bills are light gray-blue. Males in non-breeding plumage have black heads and breasts, brown bodies, and black rumps. Females are brownish overall, also with yellow eyes, and white at the base of their bills. Greater and Lesser Scaups can be difficult to distinguish in the field. Lesser Scaups average about 10% shorter and 25% lighter than Greater Scaups. The Lesser has a peaked, angular head that the Greater lacks. Seen in flight, the white on the Lesser Scaup's wings fades to gray in the primaries. In the Greater Scaup, the white extends into the primaries. As always, taking into account habitat, range, and season may help differentiate between the two species, as well as using a field guide and working with experienced observers.

Greater Scaups are Common in Western Washington from September-Mid May.

Habitat

The Greater Scaup is the more northerly of the two species of North American Scaup. In the summer, they breed on marshy, lowland tundra at the northern limits of the boreal forest. In winter, they gather in coastal bays, lagoons, and estuaries, with some wintering on inland lakes. While the Greater Scaup does overlap with the Lesser Scaup in winter, it tends to frequent more open, exposed areas.

Behavior

Outside of the breeding season, Greater Scaup form large flocks or rafts, numbering in the thousands. In tidal waters, they tend to face up-current. While individuals may drift downstream, birds from the back of the flock fly to the front, maintaining the raft in the same position. A diver, the Greater Scaup catches its food under water, but eats it on the surface. Occasionally scaups forage at or near the water's surface as well.

Female

Male