Glaucous-winged Gull
Glaucous-winged Gull
Larus glaucescens
At a Glance
The typical large gull of the northern Pacific Coast, nesting mainly from southern Alaska to Washington. Common all along the Pacific Coast in winter, it very rarely strays any distance inland. Part of a complex of closely related forms, it interbreeds freely with Western Gull at the southern end of its range, and often with Herring Gull and Glaucous Gull in Alaska.
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
Gull-like Birds, Gulls and Terns
IUCN Status
Least Concern
Habitat
Coasts and Shorelines, Lakes, Ponds, and Rivers, Landfills and Dumps, Saltwater Wetlands, Urban and Suburban Habitats
Region
Alaska and The North, California, Northwest, Southwest, Western Canada
Behavior
Direct Flight, Soaring
Population
470.000
Range & Identification
Migration & Range Maps
Present all year in much of range, but some withdrawal in winter from northernmost areas in western Alaska. Many disperse well to the south in winter, reaching northwestern Mexico. Very rare migrant inland.
Description
24-27" (61-69 cm). Bulky large gull with thick bill and pink legs, but wingtips patterned with gray, not black. Immature has wingtips pale gray-brown, not blackish as on the immatures. Often interbreeds with Western Gull on Washington coast, and hybrids are commonly seen.
Size
About the size of a Heron, About the size of a Mallard or Herring Gull
Color
Black, Gray, Pink, Red, White, Yellow
Wing Shape
Pointed, Tapered
Tail Shape
Rounded, Short, Square-tipped
Songs and Calls
A raucous series of similar notes on one pitch; also soft ga-ga notes when an intruder approaches.
Call Pattern
Falling, Flat
Call Type
Raucous, Scream
Habitat
Primarily coastal. Most common around bays, estuaries, beaches, rocky shorelines. Visits fresh ponds and garbage dumps near coast. Sometimes far offshore over continental shelf, well out of sight of land. Very rare around inland lakes and rivers. Nests mainly on low, flat islands.
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Behavior
Eggs
2-3, sometimes 1-4. Olive to yellow-green, marked with scrawls and blotches of brown and gray. Incubation is by both sexes, 26-29 days.
Young
Downy young may leave nest 2 days after hatching, remain in vicinity. Both parents feed young. Age at first flight 37-53 days after hatching; leave colony about 2 weeks later on average.
Feeding Behavior
Forages while walking or swimming, or may plunge into water from flight. May drop hard-shelled clams and crabs onto rocks while in flight to break them open. Associates with feeding bears and other predators to pick up scraps they leave behind.
Diet
Omnivorous. Diet includes fish, limpets, chitons, clams, mussels, sea urchins, barnacles, crabs, squid. Also smaller birds, eggs, small mammals, some plant material. Scavenges refuse in garbage dumps, and eats carrion.
Nesting
First breeds at age of 4 years or older. Breeds in colonies, often densely packed. Nest site is on ground, sometimes on cliff or roof. Nest (built by both sexes) is a shallow scrape lined with grass, moss, seaweed, debris. Pair may begin building several nests, but complete only one.
Conservation
Conservation Status
Has been steadily increasing in numbers in recent decades. Since it is a predator on eggs and young, its increase may cause problems for populations of other coastal bird species.
Climate Threats Facing the Glaucous-winged Gull
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.