Animal Diversity Web

Ge­o­graphic Range

Trum­peter swans are found through­out the Nearc­tic Re­gion, mainly in Alaska, Canada, and the north­ern United States. A large per­cent­age is found in Alaska, specif­i­cally in Prince William Sound and the Cop­per River Delta. Some trum­peter swans have even taken up res­i­dence in Yel­low­stone Park, Wyoming. (Grant and Hen­son, 1994; Hen­son and Cooper, 1993; Mills, 1991; Schmidt, et al., 2009; Squires and An­der­son, 1997; Squires, 1995)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Trum­peter swans live on land but al­ways in close prox­im­ity to water. They are found in wet­lands with open water and areas with many rivers or streams. Wa­ters can be salt water, fresh water, or brack­ish water. Their cli­mate ranges from tem­per­ate to polar. Rea­sons for their choice of en­vi­ron­ment have to do with their diet and nest­ing habits. Cygnus buc­ci­na­tor feeds off many plants na­tive to those areas. They are also known for lay­ing their eggs near or on the water. They seek out the same habi­tat type for win­ter­ing grounds. (Grant and Hen­son, 1994; Hen­son and Cooper, 1993; Mills, 1991; Prof­fitt, 2009; Schmidt, et al., 2009; Squires and An­der­son, 1997; Squires, 1995)

• Habitat Regions
• temperate
• polar
• terrestrial

• Terrestrial Biomes
• tundra

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

• Wetlands
• marsh

• Other Habitat Features
• riparian
• estuarine

Phys­i­cal De­scrip­tion

As the largest North Amer­i­can swans, these birds can weigh up to 13.5 kg and mea­sure ap­prox­i­mately 1.6 m in length. Wingspan can often ex­ceed 2 m. When they are young "cygnets", the bill fea­tures some de­gree of pink but is al­ways black at the base. The feet and tarsi (por­tion of the foot that makes up the ankle re­gion) may be a grey-yel­low. The body is light to dark grey, and will grad­u­ally whiten with age. At age two, most but not all of their feath­ers have turned white, ex­cept for a few on the upper por­tion of the body.

At adult­hood their feet, bill, and tarsals are black. They have pink to red mouths which can be seen as a small pink or red line (a 'grin') on the bill. Their feath­ers are com­pletely white. There is also a small per­cent­age of trum­peter swans that have a grey-white tint for feather color in­stead of pure white.

They ap­pear very sim­i­lar to tun­dra swans (Cygnus columbianus), with the most re­li­able dif­fer­ences found near the beak. Viewed face-for­ward or top-down, trum­peter swans have an an­gu­lar, v-shaped fore­head at the base of the beak. Tun­dra swans have a curved or straight fore­head. Most tun­dra swans have a yel­low-white 'teardrop' on their black beak, how­ever this is not al­ways a re­li­able field mark. (Slater, 2006)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• sexes alike

• Range mass

  9.5 to 13.5 kg

  20.93 to 29.74 lb

• Range length

  1.4 to 1.6 m

  4.59 to 5.25 ft

• Range wingspan

  2.0 to 2.4 m

  6.56 to 7.87 ft

Re­pro­duc­tion

Trum­peter swans are monog­a­mous and mate for life. Dur­ing mat­ing sea­son, trum­peter swans re­unite with their for­mer mates or begin a process of courtship to se­cure a mate. Courtship dis­plays con­sist of pairs si­mul­ta­ne­ously spread­ing or rais­ing wings, wing quiv­er­ing, head bob­bing and trum­pet­ing. (Slater, 2006)

• Mating System
• monogamous

Adults begin mat­ing at 4 to 7 years of age. Mat­ing usu­ally oc­curs from March to May. Nest-build­ing can take 2 to 5 weeks to com­plete, and both par­ents are in­volved in con­struc­tion. The nests range from 1.2 to 3.6 m in di­am­e­ter and are usu­ally sur­rounded by water. The ma­te­ri­als used in nests build­ing in­clude var­i­ous aquatic veg­e­ta­tion, grasses, and sedges.

After cop­u­la­tion and fer­til­iza­tion, the fe­males lay 4 to 6 eggs. In­cu­ba­tion lasts for 32 to 37 days, done mainly by the fe­male. The young, pre­co­cial cygnets spend their first 24 hours in the nest, then begin to swim. They fledge after 91 to 119 days and are in­de­pen­dent after one year. (Slater, 2006)

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

• Breeding interval

  Trumpeter swans breed once yearly.

• Breeding season

  Trumpeter swans breed from March to May.

• Range eggs per season

  4 to 6

• Range time to hatching

  32 to 37 days

• Range fledging age

  91 to 119 days

• Average time to independence

  1 years

• Range age at sexual or reproductive maturity (female)

  4 to 7 years

• Range age at sexual or reproductive maturity (male)

  4 to 7 years

Both par­ents con­tribute to nest build­ing which lasts 2 to 5 weeks. The fe­male will per­form the ma­jor­ity of in­cu­ba­tion. Un­like many birds, trum­peter swans do not have a spe­cial­ized brood patch and in­stead will in­cu­bate the eggs using their feet. Upon hatch­ing, the young are pre­co­cial but still re­quire sig­nif­i­cant parental care. Both par­ents care for the cygnets through­out their first year. (Slater, 2006)

• Parental Investment
• precocial
• male parental care
• female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• post-independence association with parents
• extended period of juvenile learning

Lifes­pan/Longevity

Young trum­peter swans often have sur­vival es­ti­mates from 40% to 100%, adult swan sur­vival in­creases to 80% to 100%. The old­est cap­tive trum­peter swan on record was 33 years old. In the wild, the old­est known in­di­vid­ual was 24. (Kre­mentz, et al., 1997; Slater, 2006)

• Range lifespan
  Status: wild

  24 (high) years

• Range lifespan
  Status: captivity

  33 (high) years

Be­hav­ior

Trum­peter swans live in small flocks, often with mem­bers of their own fam­ily. Their daily rou­tine varies from sea­son to sea­son. In win­ter they rest more and eat less, while in spring they con­sume large amounts of food and are very ac­tive dur­ing the day. Flock size also varies sea­son­ally. In spring, flock size can be al­most half than found in the fall be­cause the young have left and the breed­ing sea­son is about to begin.

Trum­peters are known to be very ter­ri­to­r­ial dur­ing the mat­ing sea­son. They can be­come in­cred­i­bly vi­o­lent to com­peti­tors, other swans, or any an­i­mals that could pose as a threat that in­vades their space.

Trum­peters are mi­gra­tory birds. When the weather gets colder (mid-Oc­to­ber to late No­vem­ber) they begin a slow mi­gra­tion south­ward, with the first stop usu­ally at Yel­low­stone Na­tional Park, and other parts of Wyoming and also North Dakota. They re­main there until the water freezes over and then they move onto places such as Utah and Ari­zona where the win­ter cli­mate is much warmer. Many trum­peter swans spend the win­ter on the west­ern coast of Canada, Alaska, and Wash­ing­ton. (Earnst, 1994; Slater, 2006)

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

Home Range

Trum­peter swans are very ter­ri­to­r­ial and rarely leave their nests un­guarded. Their nests are built on or near aquatic veg­e­ta­tion, and the adults do not need to wan­der far from the nest for food. Thus, the home range dur­ing the breed­ing sea­son, though not cal­cu­lated, is not ex­pected to be sub­stan­tial. (Slater, 2006)

Com­mu­ni­ca­tion and Per­cep­tion

Trum­peter swans pro­duce a va­ri­ety of sounds, but they are known for their low bugle call. In ad­di­tion to the bugle call, they also use mo­tions such as head bob­bing to alert oth­ers of dis­tur­bances or in prepa­ra­tion for flight. Trum­peter swans are very so­cial crea­tures ex­cept for in times of mat­ing, when they be­come quite ter­ri­to­r­ial. Pheromones are also used in mat­ing rit­u­als. The fe­male emits pheromones when she is ready to mate. Breed­ing pairs per­form vi­sual, syn­chro­nous dis­plays which likely re­in­force the pair-bond. Trum­peter swans call to warn the flock of im­pend­ing dan­ger. Trum­peter swans per­ceive their en­vi­ron­ment through vi­sual, au­di­tory, tac­tile, and chem­i­cal stim­uli. (Slater, 2006)

• Communication Channels
• visual
• tactile
• acoustic
• chemical

• Other Communication Modes
• duets
• pheromones

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

As cygnets, trum­peter swans' diets are mostly com­prised of aquatic in­ver­te­brates. At five weeks of age, most cygnets have con­verted to a nearly her­biv­o­rous diet. This diet con­sists mostly of tu­bers, roots, stems, leaves and oc­ca­sion­ally in­sects. In Alaska dur­ing mat­ing sea­son, the wet­land plants com­monly known as horse­tail (genus Eq­ui­se­tum) and Lyn­g­bye's sedge (Carex lyn­g­byei) are con­sumed in great quan­ti­ties. How­ever, be­cause of the wide dis­tri­b­u­tion of the species there are some vari­a­tions of their diet such as duck potato (Sagit­taria lat­i­fo­lia), water weeds (genus Elodea), pondweeds (genus Pota­moge­ton) and sago pondweed (Pota­moge­ton pecti­na­tus) tu­bers.

Trum­peter swans at­tain their food by for­ag­ing un­der­wa­ter with tails bob­bing in the air. They also yank plants out of the damp ground, with most of the plant in­tact. (Slater, 2006)

• Primary Diet
• herbivore
  • folivore

• Animal Foods
• aquatic or marine worms

• Plant Foods
• leaves
• roots and tubers

Pre­da­tion

Al­though adults ag­gres­sively de­fend their nests, ground nests are easy tar­gets for land preda­tors. Many preda­tors, such as bears, wolves and coy­otes, wolver­ines, rac­coons, and com­mon ravens are known to snatch eggs. Post-hatch­lings and adults are prey to fast preda­tors such as coy­otes, bob­cats, red foxes, and golden ea­gles. The main preda­tor of adult trum­peter swans is mankind. Hu­mans have hunted more of these swans than any­thing else.

Trum­peter swans are ag­gres­sive to­wards preda­tors, and at 12 kg with a 2 m wingspan, they can po­ten­tially in­flict se­ri­ous dam­age. Trum­peter swans do ex­hibit warn­ing be­hav­iors be­fore they at­tack, in­clud­ing head bob­bing and hiss­ing. (Kraft, 1946; Schmidt, et al., 2009; Slater, 2006)

• Known Predators

  • Man (Homo sapien sapiens)
  • Bears (Ursus)
  • Wolves (Canis)
  • Coyotes (Canis latrans)
  • Wolverines (Gulo luscus)
  • Red Fox (Vulpes vulpes)
  • Raccoons (Procyon lotor)
  • Bobcat (Lynx rufus)
  • Ravens (Corvus corax)
  • Golden Eagle (Aquila chrysaetos)

Ecosys­tem Roles

Trum­peter swans' main role in the ecosys­tem is linked to their diet. Trum­peter swans eat many in­sects when they are young. As they grow they switch to roots and aquatic plants, dig­ging around to get them which in many cases al­lows water to fill the re­main­ing holes sup­ply­ing a very valu­able nu­tri­ent to the plants. Cygnus buc­ci­na­tor can also be a host to a small num­ber of par­a­sites in­clud­ing tape­worms (Anoplo­cephala per­fo­li­ata), cae­cal paramphis­to­mids (Zy­go­cotyle lu­nata), trema­tode flukes (Echi­nos­toma rev­o­lu­tum), an­other type of trema­tode (Or­chipedum tra­che­icola), fi­lar­ial worms (a ne­ma­tode found in the heart) of the species Sar­conema eu­ryc­erca, and other forms of tape­worms (Hy­menolepis). (Cowan, 1946; Slater, 2006)

• Ecosystem Impact
• soil aeration

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Trum­peter swans used to be a com­mer­cial hunt­ing tar­get for feath­ers and skins, but over-hunt­ing led to their marked de­cline. Today, only il­le­gal hunt­ing oc­curs. (Slater, 2006)

• Positive Impacts
• body parts are source of valuable material

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Trum­peter swans are very ter­ri­to­r­ial an­i­mals, es­pe­cially dur­ing mat­ing sea­son, and hu­mans that enter their ter­ri­tory may be at­tacked. (Slater, 2006)

Con­ser­va­tion Sta­tus

His­tor­i­cally, birds were heav­ily har­vested for dec­o­ra­tive feath­ers and skins. Many birds con­tinue to be hunted il­le­gally. If birds are il­le­gally shot and do not die im­me­di­ately, an em­bed­ded bul­let may cause lead poi­son­ing and even­tual death. Today, habi­tat de­struc­tion is likely the great­est threat to trum­peter swans. Ef­forts are being made to pro­tect trum­peter swans and their wet­land habi­tat, with many states in­volved in rein­tro­duc­tion pro­grams. As mi­gra­tory birds, they are pro­tected under the United States Mi­gra­tory Bird Act.

Trum­peter swans are also af­fected by re­cent pop­u­la­tion in­creases of in­va­sive mute swans. Mute swans are markedly more ag­gres­sive and will often chase trum­peters away from their shared wet­land habi­tats. Some states are in­volved in mute swan con­trol pro­grams with the goal of re­duc­ing pop­u­la­tions to allow for na­tive swans to re­turn. (Slater, 2006)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Migratory Bird Act

  Protected

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  Threatened

Con­trib­u­tors

Kait­lyn Robins (au­thor), Rad­ford Uni­ver­sity, Karen Pow­ers (ed­i­tor), Rad­ford Uni­ver­sity, Rachelle Ster­ling (ed­i­tor), Spe­cial Pro­jects.

Ref­er­ences

Baskin, Y. 1993. Trum­peter swans re­learn mi­gra­tion. Bio­science, 43/2: 76-79.

Bergman, C. 1985. The Tri­umphant Trum­peter. Na­tional Ge­o­graphic, 168/4: 544-558.

Cowan, I. 1946. Death of a Trum­peter Swan from Mul­ti­ple Par­a­sitism. The Auk, 63/2: 248-249.

Earnst, S. 1994. Tun­dra Swan Habi­tat Pref­er­ences dur­ing Mi­gra­tion in North Dakota. The Jour­nal of Wildlife Man­age­ment, 58/3: 546-551.

Grant, T., P. Hen­son. 1994. Feed­ing ecol­ogy of trum­peter swans breed­ing in south cen­tral Alaska. Jour­nal of Wildlife Man­age­ment, 58/4: 774.

Han­son, P., J. Cooper. 1994. Noc­tur­nal Be­hav­ior of Breed­ing Trum­peter Swans. The Auk, 111/4: 1013-1018.

Hen­son, P., J. Cooper. 1993. Trum­peter Swan in­cu­ba­tion in areas of dif­fer­ing food qual­ity. Jour­nal of Wildlife Man­age­ment, 57/4: 709-716.

Johns­gard, P. 1978. The Tri­umphant Trum­peter. Nat­ural His­tory, 87/9: 72.

Kraft, F. 1946. The Fly­ing Be­he­moth is Com­ing Back. Sat­ur­day Evening Post, 219/6: 6.

Kre­mentz, D., R. Barker, J. Nichols. 1997. Sources of Vari­a­tion in Wa­ter­fowl Sur­vival Rates. The Auk, 114/2: 93-102.

La­M­on­tagne, J., L. Jack­son, R. Bar­clay. 2003. Char­ac­ter­is­tics of ponds used by trum­peter swans. Cana­dian Jour­nal of Zo­ol­ogy, 81/11: 1791-1798.

Lynch, W. 2007. Per­fec­tion in White. Cana­dian Wildlife (Cana­dian Wildlife Fed­er­a­tion), 13/4: 18-23.

Mills, J. 1991. The Swan That Would Not Fly. Na­tional Wildlife, 29/6: 4.

Prof­fitt, K. 2009. Trum­peter Swan Abun­dance and Growth Rates in Yel­low­stone Na­tional Park. Jour­nal of Wildlife Man­age­ment, 73/5: 728-736.

Schmidt, J., M. Lind­berg, D. John­son, J. Schmutz. 2009. En­vi­ron­men­tal and human in­flu­ences of trum­peter swan habi­tat oc­cu­pancy in Alaska. Con­dor, 111/2: 266/275.

Slater, G. 2006. "Trum­peter Swan (Cygnus buc­ci­na­tor): a tech­ni­cal con­ser­va­tion as­sess­ment" (On-line pdf). US For­est Ser­vice. Ac­cessed Feb­ru­ary 16, 2010 at http://​www.​fs.​fed.​us/​r2/​projects/​scp/​assessments/​trumpeterswan.​pdf.

Squires, J. 1995. Trum­peter swan (Cygnus buc­ci­na­tor) food habits in the greater Yel­low­stone ecosys­tem. Amer­i­can Mid­land Nat­u­ral­ist, 133/2: 274.

Squires, J., S. An­der­son. 1997. Changes in trum­peter swan (Cygnus buc­ci­na­tor) ac­tiv­i­ties. Amer­i­can Mid­land Nat­u­ral­ist, 138/1: 208.

Truslow, F. 1960. Re­turn of the Trum­peter. Na­tional Ge­o­graphic, 118/1: 134.

Wilkin­son, T. 1991. Call of the Trum­peter. Na­tional Parks, 66/7-8: 26.