Our Beautiful World

Trumpeter Swan, Cygnus buccinator   

Hatchlings take to the water within 48 hours and are quickly coaxed away from the nest
Photo: © Art Wolfe, National Geographic Magazine, October 1985

Trumpeters flocking to the shore of Lonesome Lake.
Photo: © Art Wolfe, National Geographic Magazine, October 1985
The Trumpeter Swan, Cygnus buccinator, is the largest native North American bird,
if measured in terms of weight and length, and is (on average) the largest waterfowl species on earth. Males typically measure from 145–163 cm (57–64 inches) and weigh 11.8 kg (26 lb);
females typically range from 139–150 cm (55–60 inches) and weigh 10 kg (22 lb).
Exceptionally large male Trumpeters can reach a length of 183 cm (72 inches),
a wingspan of 3 meters (almost 10 ft) and a weight of 17.4 kg (38 lb).
The Trumpeter Swan is closely related to the Whooper Swan of Eurasia,
and even has been considered the same species by some authorities.

Present migration routes
Photo: © Art Wolfe, National Geographic Magazine, October 1985

Their breeding habitat is large shallow ponds and wide slow rivers in northwestern and central
North America, with the largest numbers of breeding pairs found in Alaska.
Natural populations of these swans
migrate to and from the Pacific coast and portions of the United States, flying in V-shaped flocks. Released populations are mostly non-migratory.

In winter, they may eat crop remnants in agricultural fields,
but more commonly they feed while swimming.
These birds have white plumage with a long neck, a black bill subtly marked with salmon-pink
along the mouthline, and short black legs.
The females become flightless shortly after the young hatch;
the males go through this process about a month later when the females have completed their moult.

Only hours old, a cygnes surveys its surroundings from a lily pad in Alaska's Swan Creek.
In a single summer it will grow to an stounding 15 to 20 pounds.
Photo: © Art Wolfe, National Geographic Magazine, October 1985

The female lays 8 to 17 eggs in a mound of plant material on a small island,
a beaver or muskrat lodge, or a floating platform.
The same location may be used for several years.

The eggs average 73 mm (2.9 inches) wide, 113.5 mm (4.5 inches) long,
and weigh about 320 grams (11.3 oz).
The incubation period is 32 to 37 days.
These birds often mate for life, and both parents will participate in incubation and brooding.
The young are able to swim within two days and usually are capable of feeding themselves
after at most two weeks. The fledging stage is reached at 3 to 4 months.

Predators of Trumpeter Swan eggs include Common Raven (Corvus corax), Common Raccoon (Procyon lotor), Wolverine (Gulo gulo), American Black Bear (Ursus americanus), Brown Bear (Ursus arctos), Coyote (Canis latrans), Gray Wolf (Canis lupus) and Northern River Otter (Lontra canadensis).

Larger cygnets and nesting adults are preyed on by Golden Eagle (Aquila chrysaetos), Bobcat (Lynx rufus), Red Fox (Vulpes vulpes) and Coyote. Few predators, apart from the Bobcat and possibly the Golden Eagle, are capable of taking adults when they are not nesting.

One of the parents stands guard in Kenai National Wildlife Refuge.
Photo: © Art Wolfe, National Geographic Magazine, October 1985

This bird was named for its trumpet-like honk which some compare to the sound of a French horn.

In the 1800s and early 1900s, the Trumpeter Swan was hunted heavily,
both as game and a source of feathers.
These birds once bred in North America from northwestern Indiana west to Oregon in the U.S.,
and in Canada from James Bay to the Yukon, but their comparatively small numbers in the
southern part of their range were reduced to near zero by the mid-twentieth century.

Many thousands survived in the core range in Canada and Alaska, however, where populations
have since rebounded. Efforts to reintroduce this bird into other parts of its original range,
and to introduce it elsewhere, have had only modest success, as suitable habitats have
dwindled and the released birds do not undertake migrations.

Graceful flotilla of trumpeters cruises Lonesome Lake, a wintering ground in Britsh Columbia.
Photo: © Art Wolfe, National Geographic Magazine, October 1985

Text (except to pictures) : http://en.wikipedia.org


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