Black Scoter
At a Glance
Was once called 'Common Scoter,' but that name is now restricted to a similar species in the Old World. The Black Scoter is generally seen less often than the other two kinds of scoters in most parts of North America. Floats rather buoyantly on water, often with tail cocked up noticeably. On northern waters, more vocal than the other two scoters, giving clear whistled calls.
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
Near Threatened
Habitat
Coasts and Shorelines, 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
900.000
Range & Identification
Migration & Range Maps
Tends to migrate early in spring and late in fall. In migration along coast, flocks fly low over sea well offshore. When traveling overland, may make long nonstop flights at high altitude.
Description
17-21" (43-53 cm). Adult male all black except for orange bill knob. Female and young male dark, with contrasting pale face and foreneck. Winter male Ruddy Duck is smaller and paler, with relatively bigger bill.
Size
About the size of a Crow, About the size of a Mallard or Herring Gull
Color
Black, Brown, Orange, Tan
Wing Shape
Pointed, Tapered
Tail Shape
Pointed, Wedge-shaped
Songs and Calls
In spring a musical whistled cour-loo.
Call Pattern
Flat, Simple
Call Type
Croak/Quack, Whistle
Habitat
Seacoasts; in summer, coastal tundra. Breeding habitat includes low-lying wet tundra and higher slopes in treeless terrain, also openings around lakes in northern forest. In winter mostly on bays and along exposed coastlines, usually over shallow water within a mile of shore. Migrants stop on Great Lakes and other fresh waters, some remaining for winter.
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Behavior
Eggs
7-8, sometimes 5-11. Whitish to pale buff. Incubation is by female, roughly 27-33 days.
Young
Leave nest shortly after hatching and go to water. Female tends young (and broods them at night while small), but young feed themselves. Age at first flight about 6-7 weeks.
Feeding Behavior
Forages by diving and swimming underwater, propelled by feet; wings may be folded or partly opened.
Diet
Mainly mollusks, insects. At sea feeds mainly on mollusks, especially mussels and other bivalves; also crustaceans, marine worms, echinoderms. In summer on fresh water eats many aquatic insects, also fish eggs, mollusks, small fish, some plant material.
Nesting
Several males may court one female, surrounding her on water. Displays of male include rushing along surface of water with back hunched and head low, bowing jerkily while calling, and quickly snapping tail up to vertical position over back. Nest site is on ground, usually near water, often on a hummock or ridge on tundra, generally hidden by grasses or low scrub. Nest (built by female) is a shallow depression lined with plant material and with down.
Climate Vulnerability
Conservation Status
Numbers are thought to be declining. Flocks at sea are vulnerable to oil spills and other pollution.
Climate Threats Facing the Black 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.