Close up of a black-necked swan floating on a pond while sinking its head underwater searching for food

south american bird lake behavior aquatic beak habitat looking nature swan blacknecked coverts fauna feathers wings lagoon black pond searching flock underwater white peaceful vegetation exoticism palmation specie feet head neck environment native wild float food water melancoryphus cygnus plumage bill palmate delicate wilderness migration swim sink natural waterfowl migratory