The Tundra swan, also known as Cygnus columbianus, is a small swan found in the Holarctic region. There are two main types of tundra swans: Bewick’s swan (Cygnus bewickii), which lives in the Palaearctic, and the whistling swan (C. columbianus) in the Nearctic. Some birds from eastern Russia are sometimes classified as a separate subspecies, C. c. jankowskii, but many experts consider them to be part of C. c. bewickii. Tundra swans may also belong to the subgenus Olor, which includes other Arctic swans.
Bewick’s swan was named in 1830 by William Yarrell after the engraver Thomas Bewick, who created bird and animal illustrations. The name “Cygnus” is Latin for “swan,” and “columbianus” comes from the Columbia River, where the species was first identified.
C. columbianus is the smallest of the Holarctic swans, measuring 115–150 cm , with a wingspan of 168–211 cm and weighing between 3.4–9.6 kg. Adult swans of both subspecies are entirely white, with black feet. Their bills are mostly black with a thin salmon-pink line along the mouth and some yellow at the base, depending on the subspecies. They have dark brown irises. In areas with a lot of iron in the water, such as bog lakes, the head and neck may appear golden or rusty. Female swans (pens) are slightly smaller than males (cobs) but look the same.
Juvenile tundra swans are white mixed with some dull grey feathers, especially on the head and neck. As they mature, they gradually develop adult plumage. They have black bills with a large dirty-pink patch and dark grey feet with a pinkish hue. Young swans have silvery grey down feathers on their backs and white underbellies.
Bewick’s swans are the smaller subspecies, with slight size differences based on location. Their bill patterns vary, but Bewick’s swans always have more black than yellow, while whooper swans have more yellow. Each Bewick’s swan has a unique bill pattern, and researchers often create detailed drawings for identification. Eastern birds tend to be larger with less yellow on their bills.
Bewick’s swans may show color variations with different amounts of yellow, pink instead of yellow, or even yellowish feet. Their small size and shorter neck give them a resemblance to large white geese.
Tundra swans make high-pitched honking sounds, similar to a black goose (Branta). They are especially noisy when foraging in flocks during winter, calling out to each other whenever a member arrives or leaves. Despite their name, whistling swans do not produce whistles. The flight call of Bewick’s swan sounds like a low, soft ringing bark, while the whistling swan produces a different sound.
