Anseriformes

The order Anseriformes contains about 150 living species of birds in four families: the Anhimidae (the screamers), Anseranatidae (the Magpie goose), the Anatidae, which includes over 140 species of waterfowl, among them the ducks, geese, and swans and the †Vegavidae, containing the sole genus "Vegavis".
All species in the order are highly adapted to live at the water surface. All are web-footed for good swimming. While most live on water, some live mainly on land.