Bird Lore: Trumpeter Swan

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The Trumpeter Swan is the largest waterfowl native to North America, stretching to six feet in length and weighing in at 25 pounds and more. It descends upon Western Washington in mid-October. The largest numbers of this species are here between mid-November and March 1. The swans feed in farm fields by day and rest in ponds, shallow bays, and small lakes at night. This swan is occasionally seen flying over Edmonds or seen over the Sound from the Edmonds waterfront.

The adult Trumpeter Swan eats plant materials, mainly stems, leaves, and roots of aquatic plants such as pondweeds, rushes, sedges, arrowleaf and wild celery. It takes food on or above the water’s surface or from underwater by upending and extending its neck straight down, finding food by touch with its bill. In winter it also eats terrestrial grasses and waste crops in farm areas. The young eat many insects and other small invertebrates, mainly in the first two weeks after hatching.

Although pairs form between 3-4 years of age, the Trumpeter Swan does not nest for the first time until it is between 4-7 years of age. This species often mates for life. It once nested over most of North America but disappeared as human population increased and advanced westward. Most of its current breeding range is Alaska and westerns parts of Canada’s territories. There are pockets of breeding birds in western South Dakota, Minnesota and around the Great Lakes. A nonmigratory southern population exists in western Wyoming around Yellowstone National Park.

Water surrounds the nest site, which is on a small island, beaver or muskrat house, or a floating platform. Both sexes build the nest but it is thought that the female does most of the work. The nest is a low mound of plant material that is several feet in diameter. The female lays her four to six eggs in a depressed bowl in the center of the nest. Both adults incubate the eggs with the female doing most of the incubation. This species takes an unusual approach to incubation. The adults warm the eggs by covering them with their webbed feet. The eggs hatch after 32-37 days.

Young swans, or cygnets, can swim within a day of hatching. The adults tend the young and lead them to feeding sites.The young are not able to fly until they are 3-4 months old. Families migrate together to wintering grounds. The third photo shows a family of two adults and two immature birds.

Because of its size, the Trumpeter Swan needs to lumber along a 100-yard runway to get airborne. When running hard across the water’s surface, it can sound like a galloping horse as it generates takeoff speed. This is a short video of the take-off: https://www.youtube.com/watch?v=5ENpxcPBtRw. The Trumpeter Swan walks awkwardly because its short legs are set behind its center of gravity. Nonetheless, it can walk more than a mile at a time, even when traveling with cygnets less than a week old.

The oldest wild Trumpeter Swan of record was a female that was at least 26 years and 2 months of age when identified by her band in Wisconsin. There are several collective nouns for any group of swans, including ballet, bevy, drift, regatta, and school of swans.

By the 1930s, fewer than 100 Trumpeter Swans remained south of Canada. The species had been overhunted for meat, skins and feathers. The population rebounded in the northwestern part of the Lower 48, however, with protection from hunting and human disturbance. More recently the Trumpeter Swan has been reintroduced in parts of its former breeding range, including Minnesota, Wisconsin, Michigan, and Ontario. Although it is now a species of low concern for conservation purposes, the Trumpeter Swan continues to be threatened by lead poisoning, habitat loss, power lines and occasional shooting. Trumpeter Swans die every winter in Western Washington as a result of lead poisoning from shot used by hunters and sinkers used by anglers.

The linked recording is of a calling flock of Trumpeter Swans: https://www.xeno-canto.org/91642.

— By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

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