Anatidae

The Anatidae family includes ducks, geese, and swans, found on all continents except Antarctica. There are about 174 species in 43 genera. These water birds are adapted for swimming and vary in size, from the small cotton pygmy goose to the large trumpeter swan. They typically have short, pointed wings, long necks, and webbed feet, although some species, like the Nene, have lost their webbing.

Most Anatidae are herbivorous as adults, with some, like mergansers, primarily eating fish. They are generally monogamous, with breeding bonds varying from single seasons in smaller ducks to lifelong partnerships in swans and geese. The female incubates the eggs, and the young are precocial, able to feed themselves from birth. Some ducks may lay eggs in others’ nests, while the black-headed duck is a brood parasite, relying entirely on other birds to raise its young.