Tundra Swan

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Common Name: Tundra or Whistling Swan
Scientific Name: Cygnus columbianus columbianus

Size: 47-59 inches (120-150 cm); Wingspan: 67 inches (170 cm)

Habitat: North America; they breed in the coastal plains of Alaska and Canada, leaving for winter quarters about October. They arrive in winter quarters by November or December. Birds breeding in western Alaska winter along the Pacific coast from southern Alaska to California; they often move inland – particularly to the rich feeding grounds in the Californian Central Valley – and some cross the Rocky Mountains again and winter as far east as Utah and south to Texas and northern Mexico. The birds breeding along the Arctic Ocean coast migrate via Canada and the Great Lakes region to winter at the Atlantic coast of the USA, mainly from Maryland to South Carolina, but some move as far south as Florida.

Whistling Swans start leaving for the breeding grounds again by mid-March, and arrive by late May. Vagrants have been recorded on the Bermudas, Cuba the Hawaiian Islands, Puerto Rico, and in England, Ireland, Japan, northeastern Siberia and Sweden.

The species breeds near shallow pools, lakes and broad slow-flowing rivers with emergent littoral vegetation and pondweeds connected to coastal delta areas in open, moist, low-lying sedge-grass or moss-lichen Arctic tundra. It rarely nests in shrub tundra, and generally avoids forested areas. On migration, the species frequents shallow ponds, lowland and upland lakes, riverine marshes, shallow saline lagoons and sheltered coastal bays and estuaries. During the winter, it inhabits brackish and freshwater marshes, rivers, lakes, ponds and shallow tidal estuarine with adjacent grasslands, flooded pastures or agricultural arable fields.

Status: Least Concern. Global population: 170,000 adult individuals. Its numbers seem to be slowly declining in the west of its range since the late 19th century, coincident with the expansion of human settlement and habitat conversion in the birds' wintering areas; the eastern Whistling Swan populations on the other hand seem to be increasing somewhat, and altogether its numbers seem to have slightly risen in the late 20th century.

Diet: Submerged and emergent aquatic vegetation as well as grasses and grains. They often “tip up” to reach submerged aquatic vegetation and “dabble” on the water surface.

Nesting: Sexes are alike. Pens (females) are slightly smaller than cobs (males). In adult birds, the plumage is entirely white, with black feet, and a bill that is mostly black, with a thin salmon-pink streak running along the mouth line and some yellow in the proximal part. The iris is dark brown. Swans that frequent waters that contains large amounts of iron ions such as bog lakes, acquire a golden or rusty hue on their heads and necks.

Immatures are white mixed with some dull grey feathering, mainly on the head and upper neck, which are often entirely light grey; their first-summer plumage is quite white already, and in their second winter they molt into the adult plumage. Their bills are black with a large dirty-pink patch taking up most of the proximal half and often black nostrils, and their feet are dark grey with a pinkish hue. Downy young are silvery grey above and white below.

The Tundra Swans mate in the late spring, usually after they have returned to the nesting grounds; as usual for swans, they pair monogamously until one partner dies. Should one partner die long before the other, the surviving bird often will not mate again for some years, or even for its entire life.

The nesting season starts at the end of May. The pair builds the large mound-shaped nest from plant material at an elevated site near open water, and defends a large territory around it. The female lays and incubates a clutch of 3–5 eggs. The male keeps a steady lookout for potential predators. When either of them spots a threat, they give a warning sound to let their partner know that danger is approaching, Sometimes the male will use his wings to run faster and appear larger in order to scare away a predator.

The time from laying to hatching is 30–32 days. Since they nest in cold regions, Tundra Swan cygnets grow faster than those of swans breeding in warmer climates; those of the Whistling Swan take about 60–75 days to fledge. The fledglings stay with their parents for the first winter migration. The family is sometimes even joined by their offspring from previous breeding seasons while on the wintering grounds; Tundra Swans do not reach sexual maturity until 3 or 4 years of age. Cool Facts: There are two species of the Tundra Swan, the Bewick’s Swan and the Whistling Swan. C. c. columbianus is distinguished from C. c. bewickii by its larger size and the mostly black bill, with just a small and usually hard to see yellow spot of variable size at the base.

Found in Songbird Remix Waterfowl Volume 3: Swans of the World

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