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The American black duck (Anas rubripes) is a large dabbling duck in the family Anatidae.It was described by William Brewster in 1902. It is the heaviest species in the genus Anas, weighing 720–1,640 g (1.59–3.62 lb) on average and measuring 54–59 cm (21–23 in) in length with an 88–95 cm (35–37 in) wingspan.
The retention of ancestral genetic variation can be caused by incomplete lineage sorting (ILS) and introgression after secondary contact. These two factors can cause genetic variation to be shared between closely related species which is possibly why an American black duck or a Mottled duck (Anas fulvigula) may have notable white on its speculum or a Mexican duck may have flecks of green.
Mallard. When you think of ducks, the bird you picture is most likely a Mallard. This is because these ducks are seemingly everywhere, with populations spanning from South Africa to North America.
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American black duck: Iridescent violet bordered in black and may have a thin white trailing edge. [1] Northern pintail: Iridescent green in male and brown in female, both are white on trailing edge. [2] Gadwall: Both sexes have white inner secondaries. [1] Yellow-billed duck: Iridescent green or blue, bordered white. [4]
Aug. 18—MEMPHIS, Tenn. — Continental breeding duck populations are down 7% from 2022, Ducks Unlimited said Friday, Aug. 18, in reporting results from the annual spring North American waterfowl ...
They are large, black-and-white, or completely black, with long wings and deeply forked tails. The males have coloured inflatable throat pouches. They do not swim or walk and cannot take off from a flat surface. Having the largest wingspan-to-body-weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week.
This has created conservation concerns for relatives of the mallard, such as the Hawaiian duck, [124] [125] the New Zealand grey duck (A. s. superciliosa) subspecies of the Pacific black duck, [124] [126] the American black duck, [127] [128] the mottled duck, [129] Meller's duck, [130] the yellow-billed duck, [123] and the Mexican duck, [124 ...