The Mute swan (Cygnus olor) is known as an integral feature of urban parks as well as most of the waterways in our regions. But originally this beautiful white bird was a wild animal, not always with compatible behavior and habits for life in city parks. It is also amongst the heaviest of the world's flying birds.
The plumage of Mute swans is white, while the legs are dark grey. The beak is bright orange, with black around the nostrils and a black nail. Males are larger than females and have a larger knob on their bills. Young birds (cygnets) are not the bright white of mature adults, and their bill is dull greyish-black, not orange, for the first year. The down may range from pure white to grey to buff, with grey/buff the most common. The cygnets grow quickly, reaching a size close to their adult size in approximately 3 months after hatching. Cygnets typically retain their grey feathers until they are at least one year old, with the down on their wings having been replaced by flight feathers earlier that year. All Mute swans are white at maturity, though the feathers (particularly on the head and neck) are often stained orange-brown by iron and tannins in the water.
Population size
500,000
Life Span
19-40 years
Top speed
80
km/hmph
km/h mph
Weight
6.5-13
kglbs
kg lbs
Length
140-160
cminch
cm inch
Wingspan
3
mft
m ft
Mute swans breed in north-central Europe, the British Isles, and north-central Asia. They are partially migratory throughout northern latitudes in Europe and Asia, as far south as North Africa and the Mediterranean. Mute swans prefer well-sheltered bays, lakes, ponds, and open marshes.
Mute swans are usually very territorial with just a single pair on smaller lakes, though in a few locations where a large area of suitable feeding habitat is found, they can be colonial. Non-mated juveniles up to 3-4 years old commonly form larger flocks, which can total several hundred birds, often at regular traditional sites. Once the adult birds are mated they seek out their own territories and often live close to ducks and gulls. Mute swans feed during the daytime, by dabbling on the water surface and upending. While swimming they hold their neck with a graceful curve, the bill pointing downward. Mute swans are not very vocal but they do make a variety of sounds, often described as "grunting, hoarse whistling, and snorting noises." During a courtship display, they utter a rhythmic song. Mute swans usually hiss at competitors or intruders trying to enter their territory. The most familiar sound of these birds is the vibrant throbbing of the wings in flight which is unique to the species and can be heard from a range of 1 to 2 km (0.6 to 1 mi), indicating its value as a contact sound between birds in flight. Cygnets are especially vocal and communicate through a variety of whistling and chirping sounds when content, as well as a harsh squawking noise when distressed or lost. Mute swans can be very aggressive in defense of their nests and are highly protective of their mate and offspring. Most defensive acts begin with a loud hiss and, if this is not sufficient to drive off the predator or intruder, are followed by a physical attack. Swans attack by striking at the threat with bony spurs in their wings, accompanied by biting with their large bill.
Mute swans are serially monogamous and remain together for at least one season. Males may, however, have four mates, and even "divorce" to have another female. Mute swans nest on large mounds that they build with waterside vegetation in shallow water on islands in the middle or at the very edge of a lake. They often reuse the same nest each year, restoring or rebuilding it as needed. Male and female swans share the care of the nest. The breeding starts in March or early April. Nest building is done by both parents, with the male bringing the nest material to the female. Females lay 5 to 12 eggs, and incubation lasts around 36-38 days, which is done mainly by the female while her mate defends the territory. The cygnets hatch over a period of 26 hours and both parents look after the young. The female broods the cygnets and they often ride on their mother's back from the age of 10 days. Two months after hatching the young are fully feathered. They stay with their parents until the following spring and breeding season. At 3 years of age, they become reproductively mature and start to breed.
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