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
Yellow-billed Teal
Anas flavirostris
The namesake bill is bright yellow with a black tip and a black band along the ridge of the culmen. The species is somewhat similar to the larger yellow-billed pintail, but has a darker head, shorter neck and plain grayish sides.
ID text from Wikipedia, CC BY-SA 4.0
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