Greater and Lesser Scaups

Description

The Greater Scaup is a resident of the Chugach Region, occurring seasonally as an abundant migrant, a locally common breeder, and a common winter visitor. In contrast, the Lesser Scaup is a rare migrant in the Chugach Region, mostly reported only from the Copper River Delta- Cordova area.

Male Greater Scaups have a black-green chest and head with a pale blue bill, their body is white with very thin black lines and a black tail. Females are a light brown with a darker colored head and a white patch behind the blue bill. Lesser Scaups (A. affinis; egtuk [LCI]) look almost identical to Greater Scaups, but instead the males have a purple sheen to them. The Lesser Scaups also have a slight peak at the back of the head rather than the rounded head present on Greater Scaups.

Habitat and Status

Greater Scaup breed in shallow lakes and ponds in treeless areas such as tundra, often on islands or floating mats of vegetation. Spring migrants are abundant from late April to mid-May in the Copper River Delta and eastern Prince William Sound, but they are generally less numerous elsewhere in the region. Fall migrants move through the Chugach Region from early September until early November. Wintering Greater Scaups are common in several of the bays and fiords of Prince William Sound and in protected waters near unfrozen tidal flats along the outer Gulf Coast. Although Audubon models suggest a warming climate is likely to significantly decrease Scaup summer range in North America, neither winter nor summer range in the Chugach Region will be greatly impacted.

Distribution of Greater Scaup in the Chugach Region, where they are a common nesting duck in the Copper River Delta.