Indian Spot-billed Duck
Anas poecilorhyncha
This duck is around the same size as a mallard and has a scaly patterned body with a green speculum bordered by white. At rest the white stripe stands out and the long neck and the bill with yellow tip and orange red spots at the base are distinctive in the nominate subspecies. In flight it is distinguished by the green speculum with a broad white band at the base. The red spots at the base of the bills are absent in haringtoni. It measures 55–63 cm (22–25 in) in length and 83–95 cm (33–37 in) across the wings, with a body mass of 790–1,500 g (1.74–3.31 lb).
ID text from Wikipedia, CC BY-SA 4.0
Yellow-billed Duck
Anas undulata
These are mallard-sized mainly grey ducks with a darker head and bright yellow bill. The wings are whitish below, and from above show a white-bordered green speculum. Sexes are similar, and juveniles are slightly duller than adults. The north-eastern race is darker and has a brighter bill and blue speculum. It is a bird of freshwater habitats in fairly open country and feeds by dabbling for plant food mainly in the evening or at night. It nests on the ground in dense vegetation near water. Rarely, it is found in suburban areas, in close proximity to golf courses, parks and lakes or dams.
ID text from Wikipedia, CC BY-SA 4.0
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