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
Northern Pintail
Anas acuta
The northern pintail is a fairly large duck with a wing chord of 23.6–28.2 cm (9.3–11.1 in) and wingspan of 80–95 cm (31–37 in). The male is 59–76 cm (23–30 in) in length and weighs 450–1,360 g (0.99–3.00 lb), and therefore is considerably larger than the female, which is 51–64 cm (20–25 in) long and weighs 454–1,135 g (1.001–2.502 lb). The northern pintail broadly overlaps in size with the similarly widespread mallard, but is more slender, elongated and gracile, with a relatively longer neck and (in males) a longer tail.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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