Swans are the largest waterfowl, being members of the group that comprises the ducks, geese, and swans. Swans are more aquatic than geese. Both swan sexes look alike, although male cobs are slightly larger than female pens. The swan’s legs are short, and they have long necks for reaching underwater plant food. Most swan species have white plumage, except for the black swan and the black-necked swan.
Many swans are named after their calls – for example, Whooper (Cygnus cygnus), Trumpeter (Cygnus buccinator), Whistling (Cygnus columbianus columbianus), and Mute (Cygnus olor). The mute swan is a white swan with an orange-and-black bill.
The species is seen from the British Isles to eastern China. Feral populations occur in North America, Japan, Australia, South Africa, and New Zealand. Truly wild mute swans are migratory, while feral populations are sedentary.
Weighing 25 – 30 pounds and measuring 5 feet in length with an 8-foot wingspan, adult mute swans are large and unmistakable. Both sexes have all-white plumage and long necks. The profoundly curved neck and the black knob at the base of an orange bill readily identify this species. Juveniles are commonly grayish brown with gray feet and gray bill.
In flight, the motion of the wings produces a unique whistling sound that can be heard from 1 mile away. To become airborne, swans must launch from a running start of 15 to 20 feet over the water surface.
Although mute swans are generally silent, they are not “mute.” Adults have 8 – 10 different calls. They also have a resonant, loud cry (similar to that of the cranes), a solicitation call (glock, glock), given by the female to her mate, a lost call uttered when separated from other swans, and a brood call made by the female to her young.
Both sexes construct the nest. Nesting usually begins in early April, hatching in mid-May. Cygnets often ride on a parent’s back. The family group remains together. Parents provide food for cygnets by pulling up vegetation, to which insects are often attached, and dropping it on the surface.
First-year juveniles flocked together during the breeding season, wear brownish plumage, and have pinkish bills and gray feet. During their second summer, mute swans molt into white, adult-like plumage, also developing dull orange bills and small knobs. Although mute swans mate for life, re-pairing occurs if one mate dies.
Mutes are very territorial. They tolerate few trespassers on their territories, vigorously attacking other swans and waterfowl, dogs, even humans that venture too close. Their beating wings can inflict bruises, sometimes real injury to a child; the main weapon is the large wrist or joint of the wing.
- John Eastman – Eastman Guide to Birds, The: Natural History Accounts for 150 North American Species
- Guy Baldassarre – Ducks, Geese, and Swans of North America
- Catharine E. Bell – Encyclopedia of the World’s Zoos