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Copyright © Daniel Poleschook


Oct, 2011 Wintertime Swans -- by Mary Porter-Solberg, Oct 19, 2011

Trumpeter Swans, the largest of North America's native waterfowl, will soon arrive to feed in the agricultural fields and protected waters of the Sequim-Dungeness area. [Photo by Hal Everett.]

We are fortunate that we are able to observe these birds, because at the turn of the 20th century they had been hunted to near extinction. Formerly abundant and geographically widespread, Trumpeter Swan numbers were reduced greatly during the early fur trade and European settlement of North America (1600-1800s), when they were prized for their meat, skin, and primary feathers. They eventually came under the protection of the Migratory Bird Treaty Act of 1918. By 1935, only 69 swans were documented in the U.S., but unrecorded flocks also inhabited parts of Alaska and Canada. Numbers steadily have increased with habitat protection, including hunting bans and range expansion programs. By 2005, the Pacific Coast region, which spans parts of northern British Columbia and the Yukon Territory, numbered approximately 25,000 swans - about two thirds of North America's Trumpeter population of 35,000.

Our local swans are part of the Pacific Coast group. In winter, they migrate to southern British Columbia and western Washington. Although Trumpeter Swans need wetlands for breeding territory, their winter grounds are largely open fields. These wintering areas are found locally and especially in the Skagit Valley, where thousands of Trumpeters flock each fall.

Trumpeters have been known to visit Sequim since four were reported during the 1982 Christmas Bird Count. Their numbers remained in the single digits (two years reported 0) with the exception of 1986 (21), 1994 (10), and 1999 (25). By 2005, their numbers have stayed in the double digits with 57 reported in 2008, 63 reported in 2009, and 58 reported in 2010.

Trumpeter Swans form pair bonds when they are 3 or 4 years old. The pair stays together throughout the year moving together in migratory populations. They are assumed to mate for life, but some do switch mates over their lifetimes. Trumpeters lay a single clutch of three to eight eggs in a breeding season.

An adult swan has a wing span of 7-8 feet and can weigh up to 30 pounds. Wild Trumpeter Swans are known to live longer than 24 years.

Because of its long life, delayed maturation, single broods, and highly variable production, population growth of this species is sometimes slow. Although its numbers and distribution are increasing, some populations are still at risk from poor quality breeding habitat, continued loss of wintering habitat, and lead poisoning.

Sequim's Trumpeter Swans made headlines last winter, when necropsies confirmed 5 swans died from lead poisoning. Although lead is no longer legal for waterfowl hunting, the lead pellets can remain available to the birds for many years. Each time a shotgun is fired, depending on the shot shell size and load, from 200 to over 400 pellets fall to the ground where most remain available to feeding birds.

The swans pick up the lead shot when they are feeding or seeking grit in wetlands or in agricultural fields. They swallow the pellets, which are the same general size as the grit which they need to aid in the grinding of food in their gizzards. As few as three lead pellets can kill a swan.

Lead shot is still being deposited into some swan feeding areas because it remains legal for other uses. A study released in 2009 reported that since 1999, British Columbia and Washington had total documented mortality of about 2,300 swans from lead poisoning, which included about 97 percent Trumpeter Swans and a few Tundra Swans.


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