Facts about the Glaucouse-winged Gull, it is a large gull native to the Pacific coast. Glaucouse-winged Gulls are found in California year-round.
The Glaucouse-winged Gull or Glaucous winged Gull has the species name Larus glaucescens. Glaucouse-winged Gulls are called Goéland à ailes grises in French. Glaucouse-winged Gulls are called Gaviota de alas glaucas in Spanish.
The species was named by Naumann in 1840. Glaucouse-winged Gulls are a member of the Larus or gull genus and Laridae family.
The Glaucouse-winged Gull has a white chest and white head. The Glaucouse-winged Gull's back is medium gray. The Glaucouse-winged Gull has wing tips that are a medium grey, close in color to its back’s color. The Glaucouse-winged Gull's bill is yellow with a red dot near the bottom tip. The Glaucouse-winged Gull's legs are pinkish in color.
Juvenile Glaucouse-winged Gulls are light brown and gray all over. Juvenile Glaucouse-winged Gulls have black bills and dark grey legs. Glaucouse-winged Gulls gain white streaking by their first winter.
The Glaucouse-winged Gull is a large gull. The adults are 20 to 23 inches in length, with a four foot wing span. They weigh one to 1.2 kilograms or three to four pounds.
Their cry is a low cackling.
In the wild, the Glaucouse-winged Gull breed on rocky islands and coastal cliffs. Their typical nest is a scrape on the ground lined with grass, weeds, twigs and seaweed. Glaucouse-winged Gulls have been observed building nests on the roofs of buildings, especially flat roofs. The Glaucouse-winged Gull occasionally nest on peaked roofs near the chimney.
The Glaucouse-winged Gull regularly nest in colonies, including those with other gull species. Glaucouse-winged Gulls lay one to four eggs per clutch. The eggs are light green with darker striations. The young fly at four to six weeks of age, leaving the colony about two weeks after that. The Glaucouse-winged Gull breed around four years of age. Most birds in the wild live around 15 years.
The Glaucouse-winged Gull will kill and eat rabbits and pigeons, eggs, and chicks of other bird species, and sometimes chicks of their own species. The Glaucouse-winged Gull forage at sea, inter-tidal areas, beaches, and trash dumps. The Glaucouse-winged Gull will also eat marine invertebrates like crabs and mollusks, dropping them from a height onto the rocks to break them open. The Glaucouse-winged Gull will also eat fish. The Glaucouse-winged Gull will scavenge carrion like dead sea lions and at human trash dumps. The Glaucouse-winged Gull will steal food from other gulls and cormorants. The Glaucouse-winged Gull have been seen following bears to feed on the scraps they leave behind. The Glaucouse-winged Gull will feed on the waste of fishing boats and canneries.
Glaucouse-winged Gulls tend to stay along the coast. Glaucouse-winged Gulls are found in bays, estuaries, and beaches along the Pacific coast. The Glaucouse-winged Gull are periodically found around ponds and garbage dumps near the coast. The Glaucouse-winged Gull are seen over the continental coast. Glaucouse-winged Gulls are rarely found around inland lakes.
Glaucouse-winged Gulls breed in the summer in Alaska and winter in California and Baja California.
Glaucouse-winged Gulls are of least concern to the IUCN, since their numbers have been increasing since the 1950s.
Glaucouse-winged Gulls have been seen occasionally in the eastern Hawaiian islands.
The Glaucouse-winged Gull species often hybridizes with the Western Gull. Those hybrids are actually the most common gulls in Washington state and around Puget Sound.
The Glaucous winged Gull has been known to hybridize with the Herring Gull in Alaska.