The Greater Scaup (Aythya marila) or just Scaup in Europe, is a species diving duck found in northern Arctic and sub-Arctic North America and Asia. Its habitat is lakes and bogs on the tundra and at the northern limits of the boreal forest. These birds migrate further south to coastal waters in winter. In North America, Greater Scaup populations have been on a steady decline since the 1990′s. Biologists and conservationists are unsure of the reasons for decline. Some researchers believe a parasite found in snails may be to blame.
The adult is 16.5 to 20 inches in length with a 28 to 31.5 inch wingspan. It has a bluish bill and yellow eyes. The male has a dark head with a green shine, a black breast, a light back, a black tail and a white bottom. The adult female has a white band at the base of the bill and a brown head and body.
The diet of the Greater Scaup is mainly mollusks and aquatic plants. It dives and swims underwater to catch its meal. They have been reported to eat frogs as well, although this is not confirmed. The common name of this bird may have derived from its display call “˜scaup scaup”˜. It is normally silent when not breeding.