Swans
Swans Of North America, Conservation Of Swans
Swans are large birds in the waterfowl family, Anatidae, which also includes ducks and geese. There are seven species of swans, occurring on all continents except Antarctica. Three species of swan, the mute swan (Cygnus olor), the tundra swan (C. colombianus), and the trumpeter swan (C. buccinator) breed regularly in North America.
Swans have a very long neck, and all North American species have a white body. Swans are well adapted to the aquatic environment, having fully webbed feet for swimming. However, these birds are not capable of submerging; instead they feed by tipping up and using their long neck to reach for their food of aquatic plants and occasional invertebrates. The plumage and external morphology of the sexes is similar. Swans are big birds, the largest species being the mute swan, which weighs as much as 33 lb (15 kg). Swans are flightless during the molt of late summer. They generally spend this time on large lakes, where they are relatively safe from terrestrial predators.
Most species of swans undertake substantial migrations between their breeding grounds (on large ponds and lakes) and wintering grounds (lakes or estuaries), sometimes traveling thousand of miles back and forth each year. Swans are highly territorial on the breeding grounds, trumpeting loudly and often engaging in fights with other swans. They even sometimes drive other species of waterfowl from their breeding lake. Swans typically mate for life, the pair staying together until one of the spouses dies.