American Black Duck

The American black duck, Anas rubripes, is a robust member of the dabbling duck family Anatidae. It is the heaviest species within its genus, with an average weight ranging from 720 to 1,640 grams and a body length of 54 to 59 centimeters. Its wingspan stretches from 88 to 95 centimeters. The plumage is predominantly darker than that of the female and eclipse male mallard, which it resembles. Both sexes share a similar appearance, though the male is distinguished by a yellow bill, while the female's bill is a more subdued green with dark markings.

Identification Tips

In the field, one can identify the American black duck by its dark body and lighter brown head. The male's yellow bill contrasts with the female's duller green bill. The speculum is violet-blue with black margins, and the orange feet have dark webbing. When in flight, the white underwing linings are visible against the dark body. Juveniles are browner and streaked compared to adults.

Habitat

This species is native to eastern North America and is found in a variety of wetland habitats. These include freshwater and coastal wetlands, brackish marshes, estuaries, and areas with dense vegetation such as speckled alder.

Distribution

The American black duck breeds in regions from Saskatchewan to the Atlantic in Canada and in the Great Lakes and Adirondacks in the United States. It winters primarily in the east-central United States, especially in coastal areas.

Behaviour

The American black duck is partially migratory and exhibits a diverse range of behaviors. It is known to interbreed with the closely related mallard. The species is omnivorous, dabbling in shallow waters and grazing on land. It is also a valued game bird, known for its wariness and swift flight.

Song & Calls

Both sexes produce calls similar to the mallard, with the female emitting a loud quacking sequence that decreases in pitch.

Breeding

Breeding habitats include a variety of wetland environments. The female lays six to fourteen oval eggs in shades of white and buff green. Incubation is shared by both sexes and takes about 25 to 26 days, with the male defending the territory in the early stages. Ducklings are led by the hen to areas rich in invertebrates and vegetation.

Similar Species

The American black duck is often compared to the female mallard, but can be distinguished by its darker plumage and the male's yellow bill.

Diet and Feeding

The diet consists of wetland grasses, seeds, leaves, and root stalks of aquatic plants, as well as mollusks, snails, amphipods, insects, mussels, and small fishes. The proportion of animal food increases during winter and nesting periods.

Conservation status

The species is classified as Least Concern by the IUCN, though some populations are in decline. Conservation efforts include habitat management and protection, particularly in migratory stopover, wintering, and breeding areas.