From wetland to wetland Modern taxonomists group together ducks, geese and swans in the waterfowl family Anatidae, which includes the elegant, long-necked swans (Cygnus sp.), the mandarin ducks (Aix galericulata), so often seen in pairs with their mates, and the swan goose (Anser cygnoides), the long-distance messenger of Chinese folklore. From little onepound ducks to 30-pound swans, the family has almost 150 species.
近代生物學將野鴨與雁、天鵝三類水禽，統歸於「雁鴨科」，包括了長頸優雅的天鵝、比翼雙雙的鴛鴦、千里傳書的鴻雁；從一磅重的小野鴨，到三十磅的大雁鵝，有將近一百五十種。