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Mute Swan

Cygnus olor [sig' nuhs O' lor]

female Mute Swan with her young (cygnets)


Mute swans average around 57 to 60 inches in length, have a wingspan of from 6 to 8 feet, and weigh between 20 and 29 pounds. Males are generally larger than females.

The most distinguishing features of the mute swan are a black "knob" at the base up the upper bill and the color of the bill itself, which is orange, with the tip and base colored black.

close-up of mute swan showing the black knob

Distribution and Habitat

Mute swans breed in the British Isles, north-central Europe, and north-central Asia. They winter as far south as North Africa, the Neart East, and to northwest India and Korea. They live in well-sheltered bays, open marshes, lakes, and ponds.


Contrary to the stereotype of the "pining swan" who has lost its mate, mute swans do not always pair for life. In fact, some have been observed to have as many as four mates in one breeding season, and there have even been reports of a mute swan "divorcing" one mate in favor of another. Most mute swans, however, do form monogamous pairs for at least one season, and established pairs are more successful breeders than non-established pairs.

Nest sites are selected and breeding begins in March or April, depending on geographic location and prevailing weather conditions. The large nest is made of aquatic vegetation and lined with feathers and down. It is built well above the normal water level in swamp places near a pond or lake.

Five to twelve pale gray to pale blue-green eggs are laid, which are incubated for 36 to 38 days. Although both sexes share incubation duties, the female (pen) does most of the sitting, while the male (cob) stands guard. The chicks (cygnets) are brownish gray and only remain in the nest for one day. The male may take the first-hatched cygnet to the water while the female incubates the remaining eggs.

Cygnets fledge at about 60 days but remain with their parents until the next breeding season, at which time they are driven away. They will spend the next couple of years looking for suitable breeding territory and searching for a mate.


Mute swans feed on aquatic vegetation, aquatic insects, fish, and frogs.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Aves
order Anseriformes
family Anatidae
subfamily Anserinae
genus & species Cygnus olor


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The Robinson Library >> Order Anseriformes

This page was last updated on September 01, 2018.