Whilst overwintering, Bewick's swans form very large flocks and mix with other swans (7). They tend to feed on roots and foliage, often in farmland during the day, and roost on the water at night (3) (7). Individuals can be identified by the unique patterns of the bill. Studies have shown that pairs stay together for many years and should one individual die it can take up to three years for the other to find a new mate (6). It has also been shown that family groups remain together and make the migration as a group (6). During the breeding season, pairs produce between 3 and 5 eggs which are incubated for up to 30 days. The young swans, known as cygnets, will have fully fledged after a further 40-45 days (3). They stay with their parents during the first winter and often during their second too, even if the parents have produced a new brood (7).
Bewick's swan is the smallest swan to visit Britain (3). It is named after the illustrator Thomas Bewick who died in 1828 and produced many fine drawings of this species during his lifetime (5). These graceful white birds are generally very similar in appearance to the whooper swan (Cygnus cygnus
) but their bills feature a small, typically rounded patch of yellow, whereas in whooper swans the wedge-shaped patch of yellow extends below the nostril (2). Males and females are very similar in appearance, but juveniles are generally greyish in colour and the bill is pink and off-white (2). This swan often produces a musical honking, especially when they are in flocks (6).
Bewick's swan is a subspecies of Cygnus columbianus
. Another subspecies of this swan is the Tundra swan (Cygnus columbianus columbianus
), which occurs in North America (4). Bewick's swan breeds in the Arctic tundra across northern Russia. Birds from the western part of this breeding range migrate to spend the winter further south in lowland areas of northern Europe from Denmark to France and the British Isles (4). The eastern population spends the winter in China, Korea and Japan (7). In Britain the largest wintering populations are found in eastern England (4). Very large flocks occur at the Ouse Washes and in Gloucestershire at Slimbridge (6).
Kola Peninsula to arctic n Siberia; winters w Europe to s Asia.