Систематика лебедей, гусей и казарок Swan goose Pink-footed goose Greylag goose Greater white-fronted goose Lesser white-fronted goose Bar-headed goose Blue goose Snow goose Ross's goose Black brant Barnacle goose Canada goose Red-breasted goose Aleutian cackling goose Hawaiian goose Coscoroba swan Black-necked swan Black swan Mute swan Bewick's swan Whooper swan Trumpeter swan