Anseriformes is an order of birds . It comprises about 150 living species in three families : Anhimidae ( the screamers ) , Anseranatidae ( the magpie goose ) , and Anatidae , the largest family , which includes over 140 species of waterfowl , among them the ducks , geese , and swans .
The order Anseriformes contains about 150 living species of birds in three families : the Anhimidae ( the screamers ) , Anseranatidae ( the Magpie Goose ) , and the Anatidae , which includes over 140 species of waterfowl , among them the ducks , geese , and swans .