During the winter, gatherings of Trumpeter Swans (Cygnus buccinator) are a fairly common sight in the fields along the roads in Skagit and Whatcom counties of Washington State. It is even possible to catch sight of them along Interstate 5 foraging on plant material and invertebrates. These are truly impressive birds and graceful in their movements. Trumpeters are North America's largest native waterfowl, and among the heaviest of all flying birds, according to Birdweb.
As of 1900, they were thought to be extinct. By 1930, small populations were discovered in Idaho, Montana and Wyoming but fewer than 100 birds remained south of Canada. Then in the 1950's a large population was discovered in Alaska. Because of protection, habitat preservation and reintroduction they have made a comeback.
Seasonally, they are now found in greater numbers in Washington than anywhere else in the lower 48 states. The North American population is estimated to be 15-16,000 birds. In one recent census, more than 2,000 were counted here in Skagit County. Trumpeters are still under threat due to habitat loss and poisoning by lead shot, now banned in both Canada and the U.S.
A similar local visitor is the Tundra Swan (Cygnus columbianus). The differences between the two species are subtle. Sibley tells us, the Trumpeter is the larger of the two and has a larger bill. Also in the Trumpeter, the slope of the bill matches the slope of the flatter crown of the head with a sharp corner at the rear of the crown. Tundras have a rounder shaped head and often have an orange spot in front of the eye. The birds in these photos match those characteristics of the Trumpeter Swan.