The glaucous-winged gull (''Larus glaucescens'') is a large, white-headed

gull Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century ...

. The genus name is from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''Larus'' which appears to have referred to a gull or other large seabird. The specific ''glaucescens'' is

New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival of Literary Latin used in original, scholarly, and scientific works since about 1500. Modern scholarly and technical nomenclature, such as in zoological and botanical taxonomy ...

for " glaucous" from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

, ''glaukos'', denoting the grey color of its wings.

Range and lifespan

The glaucous-winged gull is rarely found far from the ocean. It is a resident from the western coast of

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

to the coast of

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

. These glaucous winged gulls can also be found in the

Puget Sound region The Puget Sound region is a coastal area of the Pacific Northwest in the U.S. state of Washington, including Puget Sound, the Puget Sound lowlands, and the surrounding region roughly west of the Cascade Range and east of the Olympic Mountains. ...

. It also breeds on the northwest coast of Alaska, in the summertime and in the

Russian Far East The Russian Far East (russian: Дальний Восток России, r=Dal'niy Vostok Rossii, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in Northeast Asia. It is the easternmost part of Russia and the Asian continent; and is admin ...

. During

winter Winter is the coldest season of the year in polar and temperate climates. It occurs after autumn and before spring. The tilt of Earth's axis causes seasons; winter occurs when a hemisphere is oriented away from the Sun. Different cultur ...

, they can be found along the coast of

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

, Baja California Sur, and Sonora. Glaucous-winged gulls are thought to live about 15 years, but some live much longer; a bird in

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

, for example, lived for more than 21 years, while one in the US state of

lived for at least 22 years, 9 months. The longevity record though, is more than 37 years, for a bird banded as a chick in British Columbia. It is an exceptionally rare vagrant to the

Western Palearctic The Western Palaearctic or Western Palearctic is part of the Palaearctic realm, one of the eight biogeographic realms dividing the Earth's surface. Because of its size, the Palaearctic is often divided for convenience into two, with Europe, North ...

region, with records from

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...

, the Canary Islands and, most recently, from

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

in February and March 2016. It has also been recorded in

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

in the winters of 2006/2007 and 2008/2009. The 2008/2009 record was from Saltholme Pools, Cleveland, and attracted hundreds of twitchers.

Description

This gull is a large bird, being close in size and shape to the closely related

Western gull The western gull (''Larus occidentalis'') is a large white-headed gull that lives on the west coast of North America. It was previously considered conspecific with the yellow-footed gull (''Larus livens'') of the Gulf of California. The western ...

(''L. occidentalis''). It measures in length and in wingspan, with a body mass of .''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), .''Gulls: Of North America, Europe, and Asia'' by Klaus Malling Olsen & Hans Larsson. Princeton University Press (2004). . It weighs around on average. Among standard measurements, the wing chord is , the

bill Bill(s) may refer to: Common meanings * Banknote, paper cash (especially in the United States) * Bill (law), a proposed law put before a legislature * Invoice, commercial document issued by a seller to a buyer * Bill, a bird or animal's beak Plac ...

is and the tarsus is . It has a white head, neck, breast, and belly, a white tail. The silver-gray wings and back form the mantle, which is darker than that of the Glaucous gull and paler than the

Herring gull Herring gull is a common name for several birds in the genus '' Larus'', all formerly treated as a single species. Three species are still combined in some taxonomies: * American herring gull (''Larus smithsonianus'') - North America * European ...

and Western Gull. The primary flight feathers (wingtips) are grey, usually the same shade as the mantle. Its legs are pink and the beak is yellow with a red subterminal spot (the spot near the end of the bill that chicks peck in order to stimulate regurgitative feeding). The irises are typically dark, and surrounded by pink orbital skin. The forehead is somewhat flat. During the winter, the head and nape is darker with a varied smudged or mottled pattern, and the bill colour becomes duller, often with dark markings near the tip. Young birds are brown or gray with black beaks, and take four years to reach adult plumage. Glaucous-winded Gull with Crab

Behaviour

The glaucous-winged gull nests in the summer, and each pair produces two or three chicks which fledge at six weeks. It feeds along the coast, scavenging for dead or weak animals, fish, mussels and scraps. In urban areas it is well known for its tendency to accept food from people and peck open unprotected garbage bags in search of edibles. Its call is a low-pitched "kak-kak-kak" or "wow", or a more high-pitched wailing. Seagull in Seattle

Hybridization

The Glaucous-winged Gull frequently hybridizes with

western gull The western gull (''Larus occidentalis'') is a large white-headed gull that lives on the west coast of North America. It was previously considered conspecific with the yellow-footed gull (''Larus livens'') of the Gulf of California. The western ...

where their ranges overlap in Washington and Oregon. In the

Puget Sound Puget Sound ( ) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected ma ...

area, hybrids may outnumber pure birds and

backcross Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, to achieve offspring with a genetic identity closer to that of the parent. It is used in horticulture, animal breeding, and product ...

with either parent species leading to further identification problems. Referred to as the Olympic gull, this hybrid is found along the Pacific coast from British Columbia south to California. Hybrids are variable and have characteristics of either parent species. Often they resemble Glaucous-winged gulls but have darker grey wingtips which strongly contrast from the mantle, and may have a heavier bill more typical of Western gulls. Hybrids also tend to exhibit dark head markings in nonbreeding plumage, compared to the virtually unstreaked white head of pure Western Gulls. The prevalence of 'Olympic gull' hybrids is an example of bounded hybrid superiority, where natural selection favours hybrids in areas of intermediate habitat. One study found that females paired with hybrid males have higher breeding success than pairs of the same species. In the central part of the hybrid zone, clutch size was larger among pairs with hybrid males, many of which established breeding grounds in more vegetative cover than pure western gull males, which preferred sand habitat resulting in heavier predation. In the northern section of the hybrid zone, there was no difference in clutch size, but breeding success is higher due to the hybrids being more similar to western gulls in foraging behaviour, feeding more on fish than glaucous-winged gulls. Little evidence of

assortative mating Assortative mating (also referred to as positive assortative mating or homogamy) is a mating pattern and a form of sexual selection in which individuals with similar phenotypes or genotypes mate with one another more frequently than would be ex ...

was observed, except for weak assortative mating among hybrids in absence of mixed species pairs. This species also hybridizes regularly with the

American herring gull The American herring gull or Smithsonian gull (''Larus smithsonianus'' or ''Larus argentatus smithsonianus'') is a large gull that breeds in North America, where it is treated by the American Ornithological Society as a subspecies of herring gul ...

in southern Alaska, sometimes referred to as the Cook Inlet Gull. This hybrid combination may be found along the Pacific coast from Alaska down to southern California, and are highly variable, sometimes resembling

Thayer's gull Thayer's gull (''Larus glaucoides thayeri'') is a subspecies of the Iceland gull. It is a large gull native to North America that breeds in the Arctic islands of Canada and winters primarily on the Pacific coast, from southern Alaska to the Gulf ...

but with a larger bill and inconsistent wing pattern. They typically have paler eyes and darker primaries than Glaucous-winged, and the winter head pattern of either parent species (Herring gull has a more streaked winter hood). Hybrids with Glaucous gull are common in west Alaska where up to 50% of birds in the Seward Peninsula are hybrids, and rare visitors further south to Japan and California. Hybrids with Slaty-backed gull are uncommon but have been known to breed on the east coast of the

Kamchatka Peninsula The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and w ...

and

Commander Islands The Commander Islands, Komandorski Islands, or Komandorskie Islands (russian: Командо́рские острова́, ''Komandorskiye ostrova'') are a series of treeless, sparsely populated Russian islands in the Bering Sea located about ea ...

, reaching south to Japan in winter.

References

External links

Detailed year-to-year plumage of the glaucous-winged gull

at ''Animal Diversity Web'' {{Taxonbar, from=Q768140

glaucous-winged gull The glaucous-winged gull (''Larus glaucescens'') is a large, white-headed gull. The genus name is from Latin ''Larus'' which appears to have referred to a gull or other large seabird. The specific ''glaucescens'' is New Latin for "glaucous" from ...

Native birds of Alaska Native birds of Western Canada Birds of North Asia