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Cygnets typically retain their grey feathers until they are at least one year old, with the down on their wings having been replaced by flight feathers earlier that year.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.
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.
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