White-winged Scoter
White-winged Scoter
Melanitta deglandi
At a Glance
The largest scoter. Flocks usually fly low over the sea in long, wavering lines, but in migration they may fly much higher, and a flock may suddenly drop hundreds of feet with a loud rushing noise. On the water, generally silent.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Diving Ducks, Duck-like Birds
IUCN Status
Least Concern
Habitat
Coasts and Shorelines, Forests and Woodlands, Lakes, Ponds, and Rivers, Open Ocean, Saltwater Wetlands, Tundra and Boreal Habitats
Region
Alaska and The North, California, Eastern Canada, Florida, Great Lakes, Mid Atlantic, New England, Northwest, Plains, Rocky Mountains, Southeast, Southwest, Texas, Western Canada
Behavior
Direct Flight, Formation
Population
400.000
Range & Identification
Migration & Range Maps
Generally migrates in small flocks, although large numbers may congregate at stopover points. On overland passage to coastal wintering areas, may fly very high. Adult males tend to winter somewhat farther north, on average, than females or younger birds.
Description
19-24" (48-61 cm). White wing patch conspicuous in flight, often hidden while swimming. Adult male has small white teardrop. Female and young male very dark, with paler face patches, pattern in front of eye different from female Surf Scoter's; at a distance, these birds are hard to tell from Surf Scoter unless the small white wing patch happens to show.
Size
About the size of a Crow, About the size of a Mallard or Herring Gull
Color
Black, Brown, Orange, White
Wing Shape
Pointed, Tapered
Tail Shape
Pointed, Wedge-shaped
Songs and Calls
Soft whistles and guttural croaks.
Call Pattern
Flat, Simple
Call Type
Croak/Quack, Whistle
Habitat
Salt bays, ocean; in summer, lakes. In breeding season around lakes, ponds, and slow-moving rivers, generally in open country. In winter mainly on coastal waters, especially shallow water over shellfish beds; some remain on Great Lakes and other large bodies of fresh water.
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Behavior
Eggs
Usually 9-10, sometimes 6-12. Pale buff or pinkish. Incubation is by female only, 25-30 days. Female covers eggs with down when leaving nest.
Young
Leave nest shortly after hatching. Female tends young and broods them while small, but young feed themselves. Age at first flight not well known, may be 9-11 weeks or as little as 7-8 weeks.
Feeding Behavior
Forages by diving and swimming underwater, propelled mainly by feet, with wings partly spread to aid in maneuvering and thrust. Small items are swallowed underwater, but large mollusks are brought to surface and swallowed whole there.
Diet
Mostly mollusks. In addition to mollusks, also feeds on crustaceans and aquatic insects, plus small numbers of fish. Also eats some plant material, including sea lettuce, pondweeds, and others.
Nesting
In courtship, several males may surround one female. Male displays include lowering head, arching back, and rushing forward short distance on water. Several males may pursue female on short underwater chases. Nesting activity begins late, with clutches often not complete until late June or early July. Nest site is on ground, usually close to water in patch of dense brush. On islands in lakes, several nests may be close together. Nest is shallow depression, sometimes with plant material added, lined with down.
Climate Vulnerability
Conservation Status
Still widespread and numerous. Wintering concentrations would be vulnerable to oil spills and other types of pollution.
Climate Threats Facing the White-winged Scoter
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.