Yellow-billed Loon
Yellow-billed Loon
Gavia adamsii
At a Glance
A big dagger-billed diving bird of wilderness waters. Closely related to Common Loon but even larger (the largest member of the family) and more northerly. Summers on high Arctic tundra, winters off wild northern shores, and occurs only in very small numbers south of Canada. Its great size, remote range, and general rarity give the Yellow-billed Loon an aura of mystery for many birders.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Duck-like Birds, Loons
IUCN Status
Near Threatened
Habitat
Coasts and Shorelines, Lakes, Ponds, and Rivers, Open Ocean, Saltwater Wetlands, Tundra and Boreal Habitats
Region
Alaska and The North, California, Northwest, Rocky Mountains, Southwest, Western Canada
Behavior
Direct Flight, Rapid Wingbeats
Population
16.000
Range & Identification
Migration & Range Maps
Most winter in limited area of southern Alaska and coastal British Columbia, but route between wintering and breeding areas unknown; may follow coast around Alaska rather than flying overland. In recent years, single birds (usually immature) have been found wintering on reservoirs and lakes in interior as far east as Illinois and Arkansas, as far south as Arizona and Texas.
Description
33-38" (84-97 cm). Bigger than Common Loon, with very heavy pale bill, the lower mandible angling up toward the tip. Often swims with bill pointed up slightly. In winter, has upper ridge of bill mostly pale (many winter Commons have pale bill but with upper ridge dark). Yellow-billed often looks paler overall, with darker ear spot.
Size
About the size of a Heron, About the size of a Mallard or Herring Gull
Color
Black, Green, White, Yellow
Wing Shape
Narrow, Pointed, Tapered
Tail Shape
Short
Songs and Calls
Yodeling calls similar to those of Common Loon but louder and harsher; generally less vocal.
Call Pattern
Complex, Rising, Undulating
Call Type
Odd, Scream, Yodel
Habitat
Tundra lakes in summer; coastal waters in winter. Breeds in high Arctic tundra region, often on large lakes but also on smaller lakes if good feeding areas are nearby; may fly up to 5 miles from nest site to feeding areas on rivers, coastal lagoons. In winter on ocean, generally on bays, inlets, among island groups; rarely on large lakes in interior.
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Behavior
Eggs
2. Brown or olive, spotted with blackish-brown. Incubation period 27-29 days; both parents incubate.
Young
Leave nest 1-2 days after hatching. Adults very aggressive in defense of downy young. Young are fed by both parents, sometimes ride on parents' backs. Second chick of brood often disappears a few days after hatching. Age at first flight not known, probably about 12 weeks. One brood per year.
Feeding Behavior
Loons do their foraging by diving from the surface and swimming underwater. They often swim along the surface with their heads partly submerged, peering about underwater, watching for prey before they dive. They are propelled mainly by their feet, but may sometimes use their wings also when turning or in bursts of speed. Loons find their food by sight.
Diet
Probably mostly fish. Diet not well known. Apparently feeds mainly on small to medium-sized fish, including sculpin, tomcod, rock cod; also crustaceans and mollusks, probably some insects in summer. Young may eat some plant material.
Nesting
May mate for life. In courtship displays, pairs dip bills in water repeatedly; splash-dive and swim past each other underwater. Nest: Male may select site, both sexes probably help build nest. Site is always very near water, on island or shore, and may be partly hidden by surrounding vegetation. Nest, often re-used from year to year, is a mound of tundra vegetation with depression at center; sometimes turf is overturned to form a mud foundation.
Climate Vulnerability
Conservation Status
World population has been estimated at under 10,000, with half of these in Alaska. Vulnerable to oil spills and other pollution in the Arctic, and to the effects of climate change.
Climate Threats Facing the Yellow-billed Loon
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.