Whooper Swan (Cygnus cygnus)
[order] Anseriformes | [family] Anatidae | [latin] Cygnus cygnus | [UK] Whooper Swan | [FR] Cygne chanteur | [DE] Singschwan | [ES] Cisne Cantor | [IT] Cigno selvatico | [NL] Wilde Zwaan | [IRL] Eala Ghlórach
spanwidth min.: 205 cm
spanwidth max.: 235 cm
size min.: 140 cm
size max.: 160 cm
incubation min.: 31 days
incubation max.: 42 days
fledging min.: 78 days
fledging max.: 96 days
eggs min.: 3
eggs max.: 5
Size is similar to the Mute Swan, but there are noticeable differences. Whooper Swans have a yellow and black beak, a more rigid neck bearing in activiy as well as at rest, and, finally, their wings produce a musical sound when they fly. Their feathers are entirely white and their webbed feet are black. Juveniles show a greyish brown plumage. After one year, they get their adult one.
The Whooper Swan can also be mistaken for the Bewick Swan whose he's very close. There are two ways to differentiate them: the Whooper Swan is much bigger, with a longer neck and a more angulous head, and the beak's yellow/black layout is different. While the Whooper's Swan beak looks globally yellow with just a black tip, the Bewick's Swan's one is mainly black with a yellow base, sometimes half yellow, half black. Unlike the Mute Swan, it never raises its wings above its back when it swims and its neck is straighter.
Winters on low agricultural land, generally not far from coast. Breeds in northern zones, on shallow fresh waters: pools, lakes and rivers in wooded country. Rarely in tundra.
Cygnus cygnus breeds mainly in Iceland, Fennoscandia and northern Russia, but winters patchily across much of Europe, which constitutes >50% of its global wintering range. Its European wintering population is relatively large (>65,000 individuals), and was stable between 1970-1990. Although there were declines in a handful of countries during 1990-2000, most European wintering populations-including key ones in Denmark and Germany-were broadly stable or increased, and the species underwent a large increase overall.
Whooper Swans nest mainly in Eurasian boreal regions. They split in three distinct groups. The most occidental one, with a stable population of about 16 000 individuals, nests in Iceland. The central one nests in Scandinavia and Occidental Russia. It is estimated at 59 000 individuals, regularly increasing. The most oriental group is located in Siberia. Its population, estimated at 17 000 individuals, is probably decreasing. These groups migrate south beginning autumn with the first cold days. The occidental group leaves Iceland for the British Isles, North Sea and Channel coasts, as far as the farthest point of Brittany. The oriental group sets up on Caspian and Black Sea shores. The Scandinavian group is the one that has the shortest migration. During winter, Whooper Swans, like Bewick Swans, spend a great deal of time grazing.
Essentially vegetarian. It eats aquatic plants and uses all parts of it (stems, leaves, roots, shoots). It also graze in prairies, like geese. It may eat small invertebrates, but it's a minor part of their diet.
This species has a large range, with an estimated global Extent of Occurrence of 10,000,000 km². It has a large global population estimated to be 180,000 individuals (Wetlands International 2002). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern. [conservation status from birdlife.org]
Pairs unite for lifetime. Males are very active in nest building. Their nest is bulky and made essentially with stems and leaves. The bottom is covered with twigs, leaves and feathers. In April-May, the female lays 4 to 7 eggs and sits on for 5 to 6 weeks. Chicks are precocious and are carried on the female's back under the male's aggressive watch and protection. Taking flight occurs 87 to 90 days after hatching.
Migratory. Part of Icelandic population remains in winter. Migrates southwards to temperate areas, sporadically in more southern latitudes in cold winters; vagrant to USA and Pakistan.