(c) Fred Atwood
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The Trumpeter Swan is North America's largest species of waterfowl.It is also the only swan found exclusively within this continent.Named for its distinct, trumpet-like call, it is widely admired today for its beauty and grace.Unfortunately, this has not always been the case, as it was driven nearly to extinction less than a century ago.The Trumpeter Swan has benefited tremendously from modern conservation efforts, but remains one of North America's least common native waterfowl species.
Weighing up to 30 pounds, with a 7 to 8 foot wingspan, the Trumpeter Swan is the largest of North America's native waterfowl.Trumpeters stand four feet tall, measuring up to five feet from bill to tail.All-white with a large black bill and dark legs, the striking adults are similar to the Tundra Swan, but generally slightly larger and bulkier, with a longer neck and more massive bill, which in the Trumpeter, is flatter, more evenly sloped, and extends back to more completely surround the eye. Individual birds are best identified by examining the details of the bill. Young birds are gray to brownish, with mottled pink and gray bills. They attain the all-white adult plumage after the first year.
Today's Trumpeter Swan population is largely based in Alaska and the western Canadian provinces, but the birds also breed locally in many areas across the Rockies and western plains. Modern range expansion is thought to be further east than the limits of their actual historic range.
A legend for the range map to the right can be found
here.
Trumpeters breed on shallow bodies of water with plenty of vegetation, including freshwater marshes, ponds, lakes, and slow moving rivers. In winter, they choose similar areas such as streams, springs, lakes, or reservoirs where vegetation and ice-free water are available. Once common breeders in prairie regions, most of the birds' present range is within forested areas.
Trumpeters are mainly herbivorous, foraging by tipping up in shallow water to reach submerged aquatic vegetation, fish, or small aquatic invertebrates. They also graze on land, particularly in winter, picking up grasses, seeds and grains, and occasionally digging for roots and tubers.
Certain characteristics of the Trumpeters' breeding biology contribute to the difficulties encountered in efforts to re-establish this species. The species is long-lived, reaching over 30 years of age. Compared to birds with shorter life spans, Trumpeters are slow to breed, so reintroduction efforts must be monitored over decades rather than seasons. While birds may pair off in their second year of life, they may not actually breed until their seventh year.
Trumpeters remain paired for life. Both parents build a very large nest, often on a raised mound, island, or even a beaver lodge. Nests can take over a month to construct. Once completed, the female lays her eggs and does much of the incubating, though the male assist. Young cygnets begin to vocalize up to 24 hours before hatching. When they emerge, wet and weakened, they are brooded by the female for another 24 to 48 hours before being led to the feeding grounds. The bulk of the young birds' diet is small aquatic animals. While cygnets can feed themselves, the parents often assist by treading in shallow water to stir up various invertebrates. Young Trumpeters cannot fly until they are 100 to 120 days old, and family groups usually remain together throughout the first winter.
Each Trumpeter population has separate migratory habits. Northern flocks generally migrate long distances toward various points along the Pacific Northwest coast. Other populations can be notoriously sedentary, often remaining on breeding grounds well beyond the onset of harsh winter conditions, a habit that can occasionally prove fatal. They will move south only as far as necessary to find sufficient open water. In spring, the course is reversed, with birds often arriving on the breeding grounds before the ice has broken up. Many reintroduced populations have yet to establish strong migratory trends. The need for additional wintering grounds away from the Yellowstone region is a current concern for the interior Trumpeter population.
Mitchell, C. D. 1994. Trumpeter Swan (
Cygnus buccinator). In
The Birds of North America, No. 105 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists' Union.
Kaufman, Kenn.
Lives of North American Birds. Houghton Mifflin Company, New York, 1996
Kortright, Francis H.
The Ducks, Geese and Swans of North America. The American Wildlife Institute, Washington D.C., 1943
Moser, T.J.
The 2005 North American Trumpeter Swan Survey. U.S. Fish and Wildlife Service. April 2006.
The Trumpeter Swan Society.
Swans Dying of Lead Poisoning in Washington State and British Columbia. . 2005.
Whan, B., Rising, G., Shea, R. "Should Trumpeter Swans Be Introduced to the Eastern United States and Canada?"
Birding 34(4): 341-343,345. August 2002.
