closeup of a black necked swan swimming in the water, tropical bird specie from south america

america american anatidae animal animals aquatic aviculture beak bill bird birds black bump closeup common cygnus exotic feathers floating fowl hump knob lake melancoryphus melanocoryphus neck necked ornithology plumage portrait red river s south specie species standing swan swans swim swimming tropical water waterfowl white zoo zoology