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Greater Scaup

Aythya marila

Diving Ducks Family

Waterfowl Identification

Male Greater Scaup
Female Greater Scaup
Similar Waterfowl:
Lesser Scaup
Greater and lesser scaup are often found together, but the larger size of the greater scaup is very obvious. Male greater scaup also have a larger more round, green-tinted head than male lesser scaup. Male greater scaup have a glossy black head tinted green. The neck, breast, and upper mantle are glossy black and the flanks and belly are white sometimes with gray vermiculations on the lower flanks. The back is whitish with fine black vermiculations and the tail, upper and under-tail coverts are black. The wing has a broad white speculum spanning nearly the length of the primaries and secondaries. The bill is a light blue-gray with a black nail, the legs and feet are gray, and the iris is yellow. Female greater scaup are brown with white oval patches around their bills. The bill is similar to that of the male, but slightly duller and the legs and feet are gray.
Typical Size:
The male and female average 18 inches in length and weigh 2 pounds. They have a wingspan of 30 inches.
The greater scaup preferred habitat is wetland areas on islands in large lakes.
Greater scaup breed on the tundra and in the boreal forest zones from Iceland across the western North American Arctic. It is estimated that three quarters of the North American population breeds in Alaska. Greater scaup lay an average of 9 eggs.
Greater scaup dive to feed on aquatic plants and animals. In coastal areas, mollusks constitute the principle items of the diet. In freshwater habitats, seeds, leaves, stems, roots, and tubers of aquatic plants are important items.
Greater scaup make extensive flights across the boreal forests of Canada prior to reaching their wintering grounds along the Atlantic coast and the Great Lakes or migrate offshore from Alaska to their wintering grounds along the Pacific coast. Occasionally observed in winter in Central America and the Caribbean.
Flyway Patterns:
The greater scaup are most commonly found along the coastal flyways.
Flight Formation:
Compact flocks fly in irregular formations. Flight is strong and direct with speeds at 50 MPH.
The males have a loud SCAUP-SCAUP and the females are usually silent.

Greater Scaup Flight and Plumage Characteristics

This guide will help you recognize Greater Scaup on the wing - it emphasizes their size, shape, and flight characteristics. The greater scaup are most commonly found along the coastal flyways and migrate late, just before freezeup. Compact flocks are the norm and movements are rapid and erratic. In flight greater and lesser scaup appear nearly identical. The wings of the lesser have a light band near the trailing edges which runs almost half way to the tip while the greater goes to the tip. Greater scaup often prefer large open water areas while lesser scaup often like marshes and ponds. The males have a loud SCAUP-SCAUP and the females are usually silent.