Trumpeter Swan
Trumpeter Swan (Cygnus buccinator)
The Trumpeter Swan (Cygnus buccinator) is a monotypic species of the genus of the swans and the family Anatidae ( Anatidae ). He owes his trumpet -like call His name. The species was threatened in the 1930s strong extinction. In 1935 it was estimated that only 69 individuals existed. The people living in remote regions in Canada and Alaska Trumpeter Swans, however, were not counted. Since then, extensive protective measures have meant that the stock has recovered. In 2000, the number of individuals was estimated at more than 23,000.
The native to North America Trumpeter Swan takes there a position that has in northern Eurasia whooper swan. Both show a similar behavior and a similar breeding biology.
Appearance
The trumpeter swan is 150-180 cm body length of the largest, if not the hardest swan. Its wingspan measures about 2.10 meters. With up to 12.5 kg of body weight, it remains slightly behind the Mute Swan ( Cygnus olor). With its white plumage and black legs, it resembles other swan species of the northern hemisphere. Trumpeter Swans have the head and neck sometimes a slightly rusty brown color tinged plumage. This is due to the fact that they often look for food in ferruginous waters. The black beak is straight. Some individuals have at the upper edge of the lower mandible to a fine red trim. Also black is the part of the face up to the eyes. Feet and legs are also black in color. Among the trumpeter swans occurs occasionally leucism. Leucistic Trumpeter swans are characterized among other things by yellowish legs and feet. The swing Mauser takes 30 to 40 days and falls in the period from June to September. During this time, the swans are flightless for about 30 days. Breeding pairs in this case have a Mauser asynchronous course.
Juveniles are initially greyish color and only gradually do.
Dissemination
The trumpeter swan was originally widespread in North America. He came from Alaska prior to Ontario and south to the Rocky Mountains and to the north of the State of Missouri. Its incidence has been reduced to several sub- areas through hunting.
A western population group breeds in Alaska, Yukon and British Columbia and winters along the coast between Alaska and the northern Oregon.
A second inland population group breeds east of the Rocky Mountains in western Canada from the Northwest Territories to Saskatchewan as well as in the area of Yellowstone National Park. The birds of this group spend the winter in Idaho and Wyoming.
In recent times, trumpeter swans were settled in several places in the Pacific Northwest again. Thanks to the dense plumage and the well-developed sebaceous glands remain the birds of these populations in the winter in the area. Settlements in the eastern U.S., however, were controversial since the historic range of the trumpeter swan is unclear. However, also in the east, the ( re) settlement succeeded.
The trumpeter swan prefers large, shallow ponds and wide slow rivers. They must have a minimum length of 100 meters, as trumpeter swans need a long run before they can rise into the air.
The IUCN estimates the total population of the trumpeter swan to about 18,000 animals. The species is not endangered.
Way of life
The end of April or beginning of May looking trumpeter swans their hatchery on. Couples start immediately to build a new nest or improve an existing one. Juveniles of the previous year close together and settle down in a body of water in which no pair broods.
Females lay one egg per day, a total of three to nine eggs in a nest from plant material on an island, on an abandoned beaver or muskrat - building, or on a floating platform. Hold the eggs for 32 days warm. In the southern area of distribution they hatch about the middle of June, in the north in early July. You use the same nesting site in some cases several years. The young can already swim shortly after hatching; fly but only after three to four months.
Trumpeter Swans feed mainly on aquatic plants. Occasionally they appear with their head under the water for food. In winter they also eat grass and grain in the fields. Young animals are fed with insects and shellfish. After a few months they switch to plant food.
In summer, adult trumpeter swans tend to moult. Temporarily they also lose their flight feathers, females about a month later when the females can fly again shortly after hatching, and males.
Of course, living trumpeter swans against the winter to the Pacific coast and the northwestern United States. They fly in a V-shaped swarm.
System
It can be distinguished for the trumpeter swan no subspecies. In the literature there are indeed indications that the breeding populations in Alaska have bigger feet than those that breed in Idaho and Montana. The observed differences may be due to different measurement methods. Studies of three populations that have their breeding area each in Alaska, Canada and Montana, reject only small genetic differences. The population in Montana is conceivable that this is due to the strong population decline at the beginning of the 20th century. However, it is not yet clear why the other two populations, individuals of which number was ( allegedly ) not so slumped, also have such great genetic similarities.
The close relationship between the individual species in the genus of the swans is demonstrated, among other things, that the individual species to interbreed in captivity. From matings between Trumpeter Swan and Mute Swan, Bewick's Swan, Whooper Swan and Pfeifschwan descendants have emerged.