Tundra Swan (Cygnus columbianus)

Because these birds breed far away from human interference, they have not had the same fate of their close relatives the trumpeter swan, which went nearly extinct from hunting and habitat destruction.

Description

Tundra or whistling swans are the largest and heaviest birds found in the Arctic, measuring over a metre long and weighing 6-7 kg. They are completely white, with the long necks and large bodies typical of swans. Individuals may have a small yellow spot at the base of the bill, in front of the eye. The skin around their faces and on their legs is dark coloured.

Distribution

Tundra swans breed in freshwater habitats across the Arctic from the treeline north to the southern Arctic islands. They winter in both freshwater and marine areas, along the Pacific coast and in the Gulf of Mexico. Tundra swan nests are found on dry elevated sites, many metres from water and occasionally on small islands.

Ecology

Tundra swans are largely vegetarian, feeding primarily on the seeds, stems, roots, and tubers of aquatic plants. Tundra swans feed by dabbling, dipping for food on the water's surface, or gleaning- picking seeds and grains off the ground. It is not uncommon to see a small group of apparently headless swans floating along, collecting food from a lake-bottom!

Predators of both immature and adult tundra swans include wolves, bears, and golden eagles. These birds are most susceptible to predation during their annual wing-molt, which renders them temporarily flightless. This species is not territorial in winter, and forms large migratory flocks that are made up of a number of family groups. Within these flocks, dominance hierarchies exist, in which older individuals take precedence at feeding and stop-over areas.