The Black Necked Swan

Native to South America, Cygnus melancoryphus, the Black-necked Swan is a close relation to the Black Swan of Australasia and the Mute Swan found in the northern hemisphere. One of the smaller members of the swan family, the Black-necked Swan is nevertheless the largest of the waterfowl to be found in South America.

Like most of its genus relatives, the Black-necked Swan is normally to be found in a wetland habitat, especially lake shorelines, lagoons and freshwater marshes. During the breeding season the Black-necked Swans are particularly abundant on the Falkland Islands, and across Patagonia (the southernmost points of Chile and Argentina). Numbers of the swan are estimated to be anywhere between 26000 and 100000, although like many other swans they are susceptible to pollution in their natural environment. Relative common, the Black-necked Swan is not under any particular threat, and has a couple of nature reserves in Chile and Argentina were it is protected.

The Black Necked Swan - Patche99z - CC-BY-SA-3.0

The Black-necked Swans are migratory although this means flying north to Paraguay and the southern regions of Brazil, during the southern hemisphere’s winter. When the swans flock together there is not the same amount of noise associated with other birds, as the Black-necked Swans are similar to the Mute Swans in that they are almost silent letting out a small whistle.

The breeding and wintering grounds both offer the types of environments where the Black-necked Swans can feed on their favoured food, namely algae, other plants, fish spawn and insects.
With sufficient food male swans can grow up to 140cm in length, with a wingspan of about 180cm. This means adult males can weigh in between 4.5kg and 6.7kg. Females are slightly smaller, and weigh a kilogram or more less than the male.

Black-necked Swan - Tony Hisgett - CC-BY-2.0

Like other members of the swan family, Black-necked swans are predominantly white, although as the name suggests the neck of the bird is black. Both male and female have greyish bills, with a red knob located just above the beak. The red knob on the male becomes larger during the mating and breeding season. Black-necked Swans will mate for life.

During the breeding season the female Black-necked Swan will lay between four and six eggs, and incubate them alone. When born the cygnets are a light grey in colour, but unlike many birds the parents will both do their turn in raising the youngster, indeed the cygnets will ride on both of the adult’s backs.

The Black-necked Swan is as beautiful and as graceful as the others in the species, and although not currently under threat will need work to ensure that it is preserved for future generations.