American Black Duck
Anas rubripes
The American black duck weighs 720–1,640 g (1.59–3.62 lb) and measures 54–59 cm (21–23 in) in length with a 88–95 cm (35–37 in) wingspan. This species has the highest mean body mass in the genus Anas, with a sample of 376 males averaging 1.4 kg (3.1 lb) and 176 females averaging 1.1 kg (2.4 lb), although its size is typically quite similar to that of the familiar mallard. The American black duck somewhat resembles the female mallard in coloration, although the black duck's plumage is darker.
ID text from Wikipedia, CC BY-SA 4.0
Mottled Duck
Anas fulvigula
The adult mottled duck is 44 to 61 cm (17–24 in) long from head to tail. It has a dark body, lighter head and neck, orange legs and dark eyes. Both sexes have a shiny green-blue speculum (wing patch), which is not bordered with white as with the mallard. Males and females are similar, but the male's bill is bright yellow, whereas the female's is deep to pale orange, occasionally lined with black splotches around the edges and near the base. The plumage is darker than in female mallards, especially at the tail, and the bill is yellower.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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