Yellow-billed Loon, immature. (c) Ron Wolf
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Perhaps more than any other bird, the Yellow-billed Loon embodies the spirit of the northern tundra. Its wild wailing cries have been described as wolf-like, and it chooses one of North America's most remote landscapes as its summer home. Unfortunately, its home is not quite remote enough to avoid human disturbance, and the birds are becoming rarer.
With its striking black and white plumage, black head, and large, pale bill, the impressive Yellow-billed Loon is the largest of the world's five loon species. It is similar in appearance to the slightly smaller and far more numerous Common Loon, which has a black bill during the breeding season. In winter plumage, separating the two species can be more challenging. The Yellow-billed Loon is generally paler, with a larger, brighter, slightly upturned bill.
As the Yellow-billed Loon is a resident of the remote Arctic tundra, exact population numbers are difficult to determine. Up to 6,000 birds (one quarter of the global population) are located within Alaska's North Slope. Further east, Yellow-billed Loons are found across the northernmost portions of Canada's Northwest Territories and western Nunavut. Away from North America, they breed across northern Siberia and winter in northern Scandinavia. The bulk of the North American winter population had been thought to migrate to the Pacific Northwest, but recent data indicates that many are trans-Pacific migrants, wintering as far away as the Yellow Sea.
A legend for the range map to the right can be found
here.
The bird's breeding habitat is the high Arctic tundra, where it nests on the shores of the region's large, remote lakes. In winter, these loons make their way to coastal waters in more temperate areas. During spring and fall migration, Yellow-billed Loons make temporary use of coastal waters, rivers, and large inland bodies of water.
The Yellow-billed Loon's diet is highly dependant upon small to medium-sized fish, which it captures by diving far below the water's surface. Mollusks, crustaceans, and other aquatic animals are also taken.
Yellow-billed Loon pairs are monogamous, returning to the same breeding territory year after year, and vigorously defending it from other loons or even smaller ducks. By mid to late June, pairs construct a mound nest of grasses, peat, and plant matter, often partially hidden in vegetation, on a lake shore, island, or raised hummock. The nest can be reused for many years. Two darkly spotted brown eggs are laid and incubated for about four weeks. Both parents help raise the chicks, which leave the nest within days of hatching. Chicks often ride on the backs of the adults, and are tended throughout the short summer.
Yellow-billed Loons depart their breeding grounds before ice sets in, sometimes as early as late August. In North America, they winter along the coasts of southeastern Alaska, British Columbia, and as far south as Washington, where they are found coastally, and less frequently, on large inland reservoirs. In 2002 and 2003, several Yellow-billed Loons from Alaska's North Slope breeding grounds were fitted with satellite transmitters. It was discovered that these birds migrated directly across the Bering Sea to Asia, where they wintered off the coasts of Japan, China, and the Korean peninsula. It is now believed that Yellow-billed Loons wintering in the Pacific Northwest are of the Canadian population, while the Alaskan population winters mainly in the Yellow Sea and Sea of Japan. Migrating in pairs or loose flocks, they arrive back at the breeding grounds by about mid-June.
Alaska Natural Heritage Program. "
Yellow-billed Loon". 2005.
Earnst, S.L. 2004. Status Assessment and Conservation Plan for the Yellow-billed Loon (
Gavia adamsii). U.S. Geological Survey, Scientific Investigations Report 2004-5258, 42 p.
Fair, Jeff. "Call of the Loon". Audubon. March 2004. 90-95.
Harrison, P. 1983.
Seabirds: an identification guide. Houghton Mifflin Co., New York, NY.
Kaufman, Kenn. 1996.
Lives of North American Birds. Houghton Mifflin Company, New York.
North, M. R. 1994. Yellow-billed Loon (
Gavia adamsii). In
The Birds of North America, No. 121 (A. Poole and F. Gill, eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists' Union.
U.S. Fish and Wildlife Service. Conservation Agreement for the Yellow-billed Loon (
Gavia adamsii). Draft for Public Review and Comment. February 2006.
