Cygnus olor

The mute swan feeds chiefly on submerged aquatic vegetation, which is obtained by upending (tipping head first into the water, so that the tail remains visible above the surface) (4). It also feeds in fields on young cereal crops (8), spilt grain (4), and on artificial food sources, such as bread given by the public (3). Territorial disputes may result in aggressive fights between males, in which they rush at one another and slide along the surface of the water (2). Pairs typically nest solitarily, although semi-domesticated birds may nest in large colonies (6) (notably at Abbotsbury in Dorset) (8). The cone-shaped nest is built at the edge of the water, and may be used in subsequent years by the same pair (4). After mid-April, between 5 and 7 (up to 12) whitish or pale blue eggs are laid. They are incubated, mainly by the female, for 35-42 days; the young, known as 'cygnets', leave the nest soon after hatching (4). Both parents take care of the cygnets for an extended period, often until the next breeding season (4).

The mute swan is Britain's largest bird (3), and one of the heaviest flying birds in the world (4); adults can weigh over 15 kg (3). The combination of their large size, very long neck, white plumage and orange-red bill with a black knob towards the top of the bill makes them easily to recognise (2). Males (cobs) and females (pens) are similar in appearance, although males are slightly larger and have a more prominent knob on the bill (4). Juveniles are greyish-brown with a grey bill, which lacks the knob seen in adults (2). Contrary to the name, the mute swan produces a range of vocalisations, including a rumbling 'heeorr', and an aggressive hissing noise when threatened (2). The wings make a loud 'clanking' in flight (8).

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Native to Eurasia. Introduced and established in North America, with breeding recorded locally from southern Saskatchewan, Great Lakes region (Michigan), southern New York and Connecticut south to central Missouri and along the Atlantic coast to Virginia; other populations have been recorded in the vicinity of Vancouver Island and in Oregon and Indiana; also in other areas of world. In the U.S., the highest winter densities occur in Michigan and along the eastern seaboard from Delaware to Massachusetts (Root 1988).

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. They are a common breeding species and permanent resident in various locations throughout Michigan and the eastern United States.

Biogeographic Regions: nearctic (Introduced ); palearctic (Native ); ethiopian (Native )

Palearctic region; winters to India and se China.

Gulf of Maine, New Zealand Exclusive Economic Zone, North West Atlantic, Polish Exclusive Economic Zone, Portuguese Exclusive Economic Zone, Spanish Exclusive Economic Zone, Swedish Exclusive Economic Zone, United Kingdom Exclusive Economic Zone, Wimereux

North America

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 )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Exotic

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

North America - from southern New England along the eastern seaboard to the mid-Atlantic. Great Lakes, and some inland populations. Europe and Asia.

Found throughout Britain, but absent from high ground and areas without fresh water (3). After 1960, the population began to decline as a result of poisoning from lead fishing weights (3). Since the mid-1980s and the banning of lead weights however, the population has increased (5). Outside of Britain, the mute swan is known throughout Europe and central Asia (6); it has also been introduced to New Zealand, Australia, South Africa, and North America (4).

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.

Range mass: 7600 to 14300 g.

Range length: 144 to 158 cm.

Range wingspan: 2 to 2.5 m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

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)

Range mass: 7600 to 14300 g.

Range length: 144 to 158 cm.

Range wingspan: 2 to 2.5 m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Length: 152 cm

Weight: 11800 grams

Length: 142.5-155 cm, Wingspan: 187.5 cm

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.

Habitat Regions: temperate ; saltwater or marine ; freshwater

Aquatic Biomes: lakes and ponds; rivers and streams; coastal

Wetlands: marsh

Other Habitat Features: estuarine

marine waters (well-sheltered bays), open marshes, and ponds

Habitat and Ecology

Systems

• Terrestrial
• Freshwater
• Marine

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

Depth range based on 15 specimens in 1 taxon.
Water temperature and chemistry ranges based on 3 samples.

Environmental ranges
  Depth range (m): 0 - 0
  Temperature range (°C): 9.408 - 11.597
  Nitrate (umol/L): 1.335 - 6.602
  Salinity (PPS): 6.428 - 34.849
  Oxygen (ml/l): 6.474 - 7.967
  Phosphate (umol/l): 0.273 - 0.484
  Silicate (umol/l): 3.994 - 9.916

Graphical representation

Temperature range (°C): 9.408 - 11.597

Nitrate (umol/L): 1.335 - 6.602

Salinity (PPS): 6.428 - 34.849

Oxygen (ml/l): 6.474 - 7.967

Phosphate (umol/l): 0.273 - 0.484

Silicate (umol/l): 3.994 - 9.916
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Comments: Open and quiet waters of lakes, ponds, marshes, and sluggish rivers, also in brackish and protected marine situations in winter (AOU 1983). Nests usually at water's edge on land or small islands, or in reed beds in shallow water, primarily in freshwater areas.

Fresh and saltwater ponds, coastal lagoons, saltwater bays.

Found in a wide range of water bodies, including rivers, lakes, ponds, reservoirs, flood waters, tidal estuaries, and sheltered coasts (4).

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

In North America, makes short local migrations or does not migrate.

Little in North America. In Eurasia, long distance migrations take place.

Mute swans eat mainly aquatic vegetation, but include small proportions of Insecta, Actinopterygii, and Lissamphibia. Mute swans plunge their head and long neck below the water's surface to graze.. 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.

Animal Foods: insects; mollusks; aquatic or marine worms

Plant Foods: leaves; roots and tubers; algae

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)

Animal Foods: insects; mollusks; aquatic or marine worms

Plant Foods: leaves; roots and tubers; algae

Primary Diet: herbivore (Folivore )

Comments: Eats mainly aquatic plants pulled up from bottom in shallow water.

Plant material mostly, aquatic and sometimes terrestrial grasses. Also consumes insects, snails, tadpoles, worms, and small fish.

Mute swans impact aquatic vegetation communities through their grazing.

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 Procyon lotor, Mustela vison, 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 (Mustela_vison)

In Great Britain and/or Ireland:
Animal / parasite / endoparasite
fluke of Cotylurus cornutus endoparasitises small intestine of Cygnus olor

Animal / parasite / endoparasite
fluke of Filicollis anatis endoparasitises small intestine of Cygnus olor

Animal / parasite / endoparasite
tapeworm of Nematoparataenia southwelli endoparasitises small intestine of Cygnus olor

Animal / parasite / endoparasite
fluke of Polymorphus minutus endoparasitises small intestine of Cygnus olor

Animal / parasite / ectoparasite / blood sucker
Theromyzon tessulatum sucks the blood of nasal passage of Cygnus olor

Animal / parasite / endoparasite
fluke of Typhlocoelum sisowi endoparasitises trachea of Cygnus olor

Mute swans impact aquatic vegetation communities through their grazing.

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)

Cygnus olor is prey of:
Amidostomum
Catatropis terrucosa

Based on studies in:
Scotland (Estuarine)

This list may not be complete but is based on published studies.

Cygnus olor preys on:
Enteromorpha
aquatic or marine worms
algae
Mollusca
Insecta

Based on studies in:
Scotland (Estuarine)

This list may not be complete but is based on published studies.

Introduced swans in southern New England occupy and defend territories against conspecific individuals year-round, except when mid-winter ice prevents occupancy. Some swans defend their territories also against waterfowl of other species, though interference with the nesting of other species has not been documented. As of the early 1990s, no impact of swans on aquatic vegetation was evident (Conover and Kania 1994).

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

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

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.

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.

Maximum longevity: 70 years (captivity) Observations: In the wild, these animals can live up to 26.8 years (http://bna.birds.cornell.edu/). There are anecdotal reports, which might be true, of animals living up to 70 years in captivity (John Terres 1980). IMR in the wild is probably less than 0.1. Breeding performance tends to decline after about age 12 (McCleery et al. 2008).

Mute swans do not mate 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 mate with only one other swan during each breeding 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 (hatchling swan) 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.

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.

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.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Average eggs per season: 5.

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)

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)

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.

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.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Average eggs per season: 5.

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)

Clutch size averages 4-6. Incubation lasts 34-38 days, mainly or entirely by female. Young are tended by both parents, independent at about 4 months.

Form pairs at 2 years old. First breed at 3-4 years old. Nest built by female, near water's edge or on small mound in shallow water. 5-7 eggs laid, incubated for 36 days mostly by the female. Both parents look after hatched young through their first winter.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 7
Specimens with Barcodes: 8
Species With Barcodes: 1

The following is a representative barcode sequence, the centroid of all available sequences for this species.

There are 7 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

Download FASTA File

The successful introduction and expansion of mute swans into North America may pose significant concerns to native wildlife. Gavia immer (threatened in Michigan) and recently re-introduced Cygnus buccinator 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 Branta canadensis and Cygnus buccinator. Wildlife managers seek to control non-native mute swans in areas where native wildlife is being threatened.

IUCN Red List of Threatened Species: least concern

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2008
  Least Concern
• 2004
  Least Concern

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)

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Winter visitor.

Canada

Rounded National Status Rank: NNA - Not Applicable

United States

Rounded National Status Rank: NNA - Not Applicable

Rounded Global Status Rank: G5 - Secure

No official conservation status. Populations in North America are increasing.

Widespread and common species, not listed under any conservation designations (3). Included in the Birds of Conservation Concern Amber List (medium conservation concern) (7).

Major Threats

Harsh winters and poisoning from lead fishing weights were responsible for the decline of the mute swan population in Britain. A series of mild winters combined with the banning of lead weights has resulted in the recovery of the numbers of this beautiful bird (5).

Management Requirements: "Egg shaking" has been used to reduce reproductive success in the northeastern U.S. where the species is regarded as a pest and threat to native waterfowl; however, negative public response has limited or eliminated the use of this technique in some areas. Rhode Island population has continued to grow despite an intensive egg-shaking program.

See Allin et al. (1987) for information on management needs in the Atlantic Flyway.

Strong lobbying to ban lead fishing weights has enabled mute swans to recover from the crash in numbers caused by lead poisoning. They will also have benefited from action carried out for other species of wildfowl, such as the creation and management of wetland nature reserves (8).

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

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.

Positive Impacts: food ; body parts are source of valuable material

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

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

Species Impact: Populations on the U.S. east coast are growing; regarded as Regarded as a pest and threat to native waterfowl in the northeastern U.S. (Allin et al. 1987).