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Black Duck swimming.

Black Duck (Anas rubripes)

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The American Black Duck is native to eastern North America, where it breeds in lakes, ponds, streams, and coastal marshes of predominantly forested landscapes. It was once considered the "bread-and-butter" duck of waterfowl hunters in the northeastern U.S. and Canada, where it typically accounted for 40% to 60% of the annual harvest. By the 1940's, however, populations began to decline, reaching all-time lows in the early 1980's. Today, numbers have stabilized somewhat, but the species is still considered a priority concern by the North American Waterfowl Management Plan. Factors responsible for the decline of Black Ducks include loss and degradation of habitat, overhunting, and interactions with the closely-related Mallard (Anas platyrhynchos), which has expanded its range into eastern North America from the Great Plains. Adult Black Ducks feed on seeds and tubers of aquatic plants, in addition to animals foods like snails and mussels along the coast. Ducklings feed exclusively on mosquito larvae and other aquatic invertebrates during their first two weeks, making them vulnerable to environmental contamination by toxic chemicals.

Hybridization with the genetically dominant Mallard is believed to be a significant threat to populations of American Black Ducks. Since 1940, nearly 1.7 million Mallards have been released in game farms within the range of the Black Duck, and native Mallard populations have moved eastward into the open landscapes created by forest clearing. Winter feeding at places like the Bay Beach Wildlife Sanctuary brings both species in contact during the spring courtship period. The Black Duck shown in this picture appears to contain some Mallard ancestry, as evidenced by the greenish feathers in the head region. If interbreeding with Mallards continues over many years, it is conceivable that the American Black Duck might by "hybridized into extinction" much in the same way that the Red Wolf has been affected by expanding Coyote populations in the southeastern U.S.

 

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Last updated on May 12, 2014