Greater Scaup

Aythya marila

Order ANSERIFORMES - Family ANATIDAE - Subfamily Anatinae

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1. Cool Facts
2. Description
3. Similar Species
4. Sound
5. Range
6. Habitat
7. Food
8. Behavior
9. Reproduction
10. Conservation Status
11. Other Names

The Greater Scaup is found primarily along the seacoast and on large bodies of water. Unlike its look-alike relative the Lesser Scaup, the Greater Scaup is found across Eurasia as well as North America.

Cool Facts

• Occasionally an older female Greater Scaup will have male-like head color and male patterning on her back, but she still has the typical white face patch of a female.
• Once incubation begins, the male Greater Scaup leaves the female and goes to molt on some relatively large, isolated lake. These lakes are used year after year during molt, and may be in the immediate vicinity of the breeding wetlands or many miles away. They are relatively shallow and contain abundant food and suitable cover.

• The nest of a Greater Scaup is usually lined with a thick layer of down plucked by the mother from her own breast. Nests of poor-condition females may lack down and instead may contain small, grayish-white feathers plucked from beneath the outer body feathers.

Description

• Size: 39-56 cm (15-22 in)
• Wingspan: 72-79 cm (28-31 in)
• Weight: 726-1360 g (25.63-48.01 ounces)

• Medium-sized diving duck.
• Rounded head.
• Bill bluish with black tip.
• Male with black head, chest, and rear end, and gray sides (black on the ends and white in the middle).
• Female dull brown, with white patch on face at base of bill.

• White stripe in wings extends out onto hand portion.
• Eyes yellow.
• Legs grayish, with black webs, joints, and back of legs.

Sex Differences

Breeding male bold black-and-white; female drabber and more brown with white patch at base of bill.

Male

Breeding (Alternate) Plumage: Head, neck, upper back, and breast black; head with greenish iridescence. Back white to gray, covered with thin, black wavy lines. Rump black. Belly white. Sides white, with some fine dark streaks. Undertail black.
Nonbreeding (Basic) Plumage: Similar to female, but with only a few white feathers on face instead of a large white patch. Head and neck blackish brown, lighter on cheeks and chin. Breast dark with some white edging to feathers. Back brown with white edges to feathers. Underparts mottled brownish and white. Tail dark grayish.

Female

White area at base of bill. Head and neck dark brown with some light mottling. Back darkish brown with white flecks. Breast buffy brown. Belly whitish. Sides and flanks brown. Tail dark brown.

Immature

Similar to adult female.

Similar Species

• Lesser Scaup extremely similar, but is slightly smaller, has bump on back of head instead of a smoothly rounded head, a smaller black nail on the bill tip, and has white stripe extending only halfway out wing. Male Lesser Scaup shows purplish or sometimes greenish sheen on head and usually duller white sides.
• Male Ring-necked Duck has black back, white shoulder, and a pronounced bump on the back of the head. Female shows ring around her eyes and a white spot on the bill.

Sound

Male makes a soft, fast whistle. Female makes hoarse, raspy "arr-arr-arr."

»listen to songs of this species

Range

Summer Range

Breeds from Alaska to Labrador, and in scattered localities across Canada. Also across northern Eurasia.

Winter Range

Winters primarily on Pacific and Atlantic coasts from Alaska to Baja California, and from Newfoundland to Texas. Also on Great Lakes and other unfrozen large lakes. Also in Eurasia.

Habitat

Found on lakes, ponds, and bays. Mostly marine in winter.

Food

Clams, snails, crustaceans, aquatic insects, seeds, and aquatic plants.

Behavior

Foraging

Dives under water to capture food.

Reproduction

Nest Type

Bowl-shaped depression in ground, usually lined with grasses and a thick layer of down. Placed in tall grass in an area not subject to flooding.

Egg Description

Brownish olive-buff.

Clutch Size

Usually 8-9 eggs. Range: 5-13.

Condition at Hatching

Downy and eyes open. Leave nest as soon as they are dry. Feed themselves immediately.

Conservation Status

Because of similarities to abundant Lesser Scaup, accurate winter counts difficult to obtain. Populations may be declining.

Other Names

Fuligule milouinan (French)
Porron bastardo, Buixot (Spanish)
Scaup (British) (English)

Sources used to construct this page:

Kessel, B., D. A. Rocque, and J. S. Barclay. 2002. Greater Scaup (Aythya marila). In The Birds of North America, No. 650 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA