A
large, dark, dabbling duck of eastern ponds and marshes. Can
be found on any body of water. Tends to prefer wooded ponds inland
and salt marshes and estuaries, especially in winter, throughout
coastal parts of its range. Named for its overall dark plumage,
its scientific species name, rubripes, is derived from its red
leg color.
Identification:
Our
darkest dabbling duck, the American Black Duck is chocolate brown
with a paler neck and head. The bill is dusky yellow on males
and a darker olive on females. In flight, it is the only regularly
occurring North American duck to show bright white underwings.
It also lacks a white border of its speculum (wing patch)-a mark
that easily separates it from female Mallards. Care must also
be taken when identifying American Black Ducks in city and town
parks as they tend to hybridize with the closely related Mallard.
Distribution
and Population Trends:
A
bird of the northeastern Neararctic, the American Black Duck
breeds across eastern Canada south to the mid Atlantic states.
Northern populations migrate as far south as the Gulf Coast where
they are seen infrequently during winter. Populations dropped
significantly between the 1950's and the 1980's so that there
are only about 50% as many birds now as there were before 1950.
Ecology:
Nests
are usually in close proximity to water, but the species can
nest up to one mile from water. Typical nest is built on or in
close proximity to the ground and is nothing more than a depression
lined with soft plant material. Sometimes nests in tree cavities.
Usually lays 7-11 eggs with rare extremes as few as 4 and as
high as 17. Young are born with downy feathers and can swim and
feed for themselves almost immediately after hatching.
Threats:
Large
scale clearing of forests for agriculture and development has
negatively affected this species of woodland lakes. Such practices
have provided suitable habitat for Mallards to move in and effectively
take over American Black Duck populations. The two species frequently
hybridize and this is thought to be another source of the American
Black Duck decline.
Conservation:
From
1977 to 1981 legal action was taken to reduce the hunting harvest
by 25%. Similar restrictions were placed on this species in Canada
after 1986. Several organizations such as the Black Duck Joint
Venture, the American Black Duck Symposium, and the Atlantic
Coast Joint Venture have focused on protecting hundreds of thousands
of hectares of habitat from 1986 to 1998.
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