Both sexes have yellow irises and long, whitish wing stripes. Also known as "Bluebill", the "Greater Scaup" is a small, handsome diving duck. The name may come from "scalp", a Scottish and Northern English word for a shellfish bed.
Uniform dark brown with white patch at the base of her bill.
The "Greater Scaup" breeds in Alaska and northern Canada, east to Hudson Bay and, occasionally, the Maritime Provinces.
Calls or song.
Usually silent, discordant croaking calls, "scaup, scaup" can be heard on the breeding grounds.
Population and distribution.
More common than the "Lesser Scaup", the "Greater" is usually seen in large rafts on large lakes and coastal bays in the northern United States. However, populations have been on a steady decline since the 1990s. Biologists and conservationists are unsure of the reasons. Some believe a parasitic trematode found in snails may be to blame. And although it is hunted, the "Greater Scaup" is not considered a choice game bird. These ducks winter along all three coasts.
The "Greater Scaup" female lays 8-12 buff-olive eggs in a down-lined cup of grass, which she conceals in marsh vegetation.