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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.
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]
When it spins its cocoon, each larva produces an exceedingly long, slender thread of silk. The larvae feed on mulberry leaves and in Europe, only one generation is normally raised each year as this is a deciduous tree. In China, Korea and Japan however, two generations are normal, and in the tropics, multiple generations are expected.
This is a list of the breeds of domestic duck which have official recognition at national or international level. [1]Most breeds of duck derive from the wild mallard, Anas platyrhynchos, while a small minority are descendants of the Muscovy duck, Cairina moschata.
The Black Duck Joint Venture is a conservation partnership established in 1989 to stabilize and restore the population of the American black duck (Anas rubripes). [1] [2] It consists of government and non-governmental agencies and organizations in Canada and the United States. [3]
American wigeon: Mareca americana (Gmelin, JF, 1789) 92 Amsterdam wigeon: Mareca marecula (Olson & Jouventin, 1996) (E) 93 African black duck: Anas sparsa Eyton, 1838: 94 Yellow-billed duck: Anas undulata Dubois, CF, 1838: 95 Meller's duck: Anas melleri Sclater, PL, 1865: 96 Pacific black duck: Anas superciliosa Gmelin, JF, 1789: 97 Laysan duck ...
The southern pochard (Netta erythrophthalma) is a species of duck, and a member of the genus Netta.There are two subspecies, the South American (southern) pochard N. e. erythrophthalma (Wied-Neuwied, 1833) and the African (southern) pochard N. e. brunnea (Eyton, 1838).