Animal Diversity Web

Ge­o­graphic Range

Mute swans breed in the British Isles, north cen­tral Eu­rope and north cen­tral Asia. They win­ter as far south as North Africa, the Near East, and to north­west India and Korea. They have been suc­cess­fully in­tro­duced in North Amer­ica, where they are a wide­spread species and per­ma­nent res­i­dents in many areas. (Reilly, 1968; Granlund, McPeek, and Adams, 1994)

• Biogeographic Regions
• nearctic
  • introduced
• palearctic
  • native
• ethiopian
  • native

Habi­tat

Mute swans are the most com­mon swans in the wild, in parks or on coun­try es­tates in their na­tive range. In win­ter, they are more com­mon on ma­rine wa­ters. They live in well-shel­tered bays, open marshes, lakes, and ponds. (Reilly, 1968; Ter­res, 1980)

• Habitat Regions
• temperate
• saltwater or marine
• freshwater

• Aquatic Biomes
• lakes and ponds
• rivers and streams
• coastal

• Wetlands
• marsh

• Other Habitat Features
• estuarine

Phys­i­cal De­scrip­tion

Mute swans are large birds, mea­sur­ing 144 to 158 cm. The wingspan is 2 to 2.5 me­ters. The two sexes are alike in ap­pear­ance, ex­cept that males are gen­er­ally larger than fe­males. The plumage is white. They are best dis­tin­guished from North Amer­i­can swans by the knob at the base of the upper bill, and the color of the bill it­self, which is or­ange, with the tip and base col­ored black. The head and neck may some­times be stained brown from water and mud con­tain­ing iron. (Reilly, 1968; Ter­res, 1980)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger

• Range mass

  7600 to 14300 g

  267.84 to 503.96 oz

• Range length

  144 to 158 cm

  56.69 to 62.20 in

• Range wingspan

  2 to 2.5 m

  6.56 to 8.20 ft

Re­pro­duc­tion

Adults are not paired for life, con­trary to the stereo­type of the 'pin­ing swan' who has lost its mate. In fact, some have been ob­served to have as many as four mates, or even 'di­vorce' one mate in favor of an­other. How­ever, es­tab­lished pairs are more suc­cess­ful breed­ers than non-es­tab­lished pairs and mute swans do form monog­a­mous pairs for at least a sea­son.

• Mating System
• monogamous

Mute swans rarely nest in colonies. Nest sites are se­lected and breed­ing be­gins in March or early April. These swans ei­ther build a new nest or use a pre­vi­ously con­structed mound, such as a muskrat house. The nest is large, made of aquatic veg­e­ta­tion, and lined with feath­ers and down. It is built well above the nor­mal water level in swampy places near a pond or lake. It is pos­si­ble for clutches of 5 to 12 to occur, but 5 to 7 is most com­mon. The eggs are pale gray to pale blue-green. In­cu­ba­tion lasts 36 to 38 days. The chicks are brown­ish gray (grad­u­ally turn­ing white within the next 12 months) and only re­main in the nest for one day. The male may often take the first-hatched cygnet to the water while the fe­male con­tin­ues to in­cu­bate the re­main­ing eggs. They are able to fly in about 60 days. Chicks can ride on the backs of their par­ents or under their wings. By the fol­low­ing breed­ing sea­son the par­ents drive the young away. The cygnets then join flocks of other non-breed­ing swans, and dur­ing this time molt their feath­ers, be­com­ing flight­less for a short pe­riod of time. In the next two years, the cygnets begin to bond with a mate and begin to look for suit­able breed­ing ter­ri­tory. Swans do not begin to breed until about their third year. (Granlund, McPeek and Adams, 1994; Reilly, 1968; Ter­res, 1980; http://​www.​airtime.​co.​uk/​users/​cygnus/​muteswan.​htm; http://​www.​aztec.​inre.​asu.​edu/​phxzoo/​swanmute.​html)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• oviparous

• Breeding interval

  Mute swans breed once yearly.

• Breeding season

  Breeding begins in March and April.

• Range eggs per season

  5 to 12

• Average eggs per season

  5-7

• Average eggs per season

  5

  AnAge

• Range time to hatching

  36 to 38 days

• Average fledging age

  60 days

• Average time to independence

  12 months

• Average age at sexual or reproductive maturity (female)

  3 years

• Average age at sexual or reproductive maturity (male)

  3 years

The sexes share in­cu­ba­tion, though the fe­male spends the ma­jor­ity of time sit­ting, and the male usu­ally stands guard.

Even in semi-do­mes­ti­ca­tion, the nest is strongly de­fended; swans have been known to at­tack other wa­ter­fowl and even peo­ple. Blows from their pow­er­ful wings can be es­pe­cially painful. They can be dan­ger­ous to chil­dren, and are ca­pa­ble of killing or maim­ing some of the larger preda­tors.

• Parental Investment
• precocial
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • protecting
    • male
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifes­pan/Longevity

The great­est age recorded for a banded mute swan was 19 years. In cap­tiv­ity, they have lived 30 to 40 years.

• Range lifespan
  Status: wild

  19 (high) years

• Range lifespan
  Status: captivity

  30-40 (high) years

• Average lifespan
  Status: wild

  321 months

  Bird Banding Laboratory

Be­hav­ior

There is no mass mi­gra­tion, though in win­ter there may be gath­er­ings num­ber­ing more than 100 in­di­vid­u­als in open salt water. When swim­ming, a mute swan holds its neck in a grace­ful curve with the bill point­ing down­ward, as op­posed to other swans, which carry their bills level and necks erect. Top flight speed is 50 to 55 mph.

(Granlund, McPeek and Adams, 1994; Reilly, 1968; Ter­res, 1980; http://​www.​airtime.​co.​uk/​users/​cygnus/​muteswan.​htm)

• Key Behaviors
• flies
• natatorial
• diurnal
• motile
• migratory
• territorial
• social

Home Range

Mute swans set up large ter­ri­to­ries of 4 to 10 acres, which can in­clude an en­tire small lake or pond.

Com­mu­ni­ca­tion and Per­cep­tion

Mute swans have keen vi­sion and hear­ing. Mute swans are usu­ally silent, as the name sug­gests. Adults some­times snort and make hiss­ing noises or puppy-like bark­ing notes or whis­tles, though the sounds are not far-reach­ing due to their straight tra­chea. Also, the sound of the wings dur­ing flight, which has been de­scribed as a mu­si­cal throb­bing or hum­ming, is very au­di­ble. They also use vi­sual dis­plays as a form of com­mu­ni­ca­tion, such as pos­tures. For ex­am­ple, in an ag­gres­sive pos­ture, males often arch their sec­ondary wing feath­ers over the back.

• Communication Channels
• visual
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

The diet of mute swans con­sists of aquatic veg­e­ta­tion, and small pro­por­tions of aquatic in­sects, fish, and frogs. Mute swans do not dive, in­stead they plunge their head and long neck below the water's sur­face. Swans feed in deeper wa­ters than ducks and other wa­ter­fowl that share their habi­tat and thus do not com­pete with them di­rectly for food. Rather, food is made more read­ily avail­able to other birds by swans be­cause parts of the plants they con­sume float to the sur­face while the swans are feed­ing. How­ever, mute swans com­pete with other swans for food be­cause they feed in sim­i­lar ways. (Reilly, 1968; Ter­res, 1980; http://​aztec.​inre.​asu.​edu/​phxzoo/​swanmute.​html)

• Primary Diet
• herbivore
  • folivore

• Animal Foods
• insects
• mollusks
• aquatic or marine worms

• Plant Foods
• leaves
• roots and tubers
• algae

Pre­da­tion

Mute swans are large and ag­gres­sive birds. As adults they are not often preyed on un­less they are old or ill. Eggs and hatch­lings are vul­ner­a­ble to nest pre­da­tion by rac­coons, mink, and a wide va­ri­ety of other medium to large-sized preda­tors. But swan par­ents are typ­i­cally pre­sent to pro­tect their young.

• Known Predators

  • raccoons (Procyon lotor)
  • American minks (Neovison vison)

Ecosys­tem Roles

Mute swans im­pact aquatic veg­e­ta­tion com­mu­ni­ties through their graz­ing.

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Mute swans were do­mes­ti­cated for food in Britain. Mark­ings on their feet in­di­cated own­er­ship. Even­tual do­mes­ti­ca­tion saved the bird from be­com­ing hunted to ex­tinc­tion there. Feath­ers were also used as quills for writ­ing, the leath­ery web used for purses, and the wing bones for mak­ing whis­tles. ( http://​www.​airtime.​co.​uk.​users/cygnus/muteswan/htm)

• Positive Impacts
• food
• body parts are source of valuable material

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Swans may at­tack peo­ple who ap­proach their nests too closely. There are records of them knock­ing boaters off of jet skis. An adult swan can se­ri­ously in­jure chil­dren.

In ad­di­tion, mute swans are thought to pose a threat to na­tive wildlife as a re­sult of com­pe­ti­tion for food, ter­ri­to­ries, and nest­ing areas.

• Negative Impacts
• injures humans

Con­ser­va­tion Sta­tus

The suc­cess­ful in­tro­duc­tion and con­se­quent ex­pan­sion of mute swans into North Amer­ica has begun to pose sig­nif­i­cant con­cerns to na­tive wildlife. Com­mon loons (threat­ened in Michi­gan) and re­cently re-in­tro­duced trum­peter swans are two species of pri­mary con­cern. The North Amer­i­can pop­u­la­tion of mute swans has been in­creas­ing steadily since its in­tro­duc­tion. These birds are ag­gres­sive, and have been known to drive off such stub­born and sim­i­larly sized species as Canada geese and trum­peter swans. Wildlife man­agers seek to con­trol non-na­tive mute swans in areas where na­tive wildlife is being threat­ened. (Granlund, McPeek, and Adams, 1994)

There was a high in­ci­dence of lead poi­son­ing in the mute swans of Great Britain, caused by the swans' in­ges­tion of dis­carded lead shot that be­came en­tan­gled in aquatic veg­e­ta­tion. Since this prob­lem was dis­cov­ered, it is no longer a major threat to mute swan pop­u­la­tions in Britain. ( http://​www.​airtime.​co.​uk/​users/​cygnus/​muteswan.​htm)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Migratory Bird Act

  No special status

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Con­trib­u­tors

Tanya Dewey (ed­i­tor), An­i­mal Di­ver­sity Web.

Ali­cia Ivory (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Granlund, J., McPeek, G., and Adams, R. The Birds of Michi­gan. In­di­ana Uni­ver­sity Press, In­di­anapo­lis, 1994.

Hal­ton, W. http://​www.​airtime.​co.​uk/​users/​cygnus/​muteswan.​htm

Reilly, E. The Audubon Il­lus­trated Hand­book of Amer­i­can Birds. Mc­Graw-Hill Book Com­pany, New York, 1968.

Ter­res, J. The Audubon So­ci­ety En­cy­clo­pe­dia of North Amer­i­can Birds. Al­fred A. Knoph, New York, 1980.

http://​aztec.​inre.​asu.​edu/​phxzoo/​swanmute.​html