The
Common Gull,
Mew Gull or
Sea Mew (
Larus canus) is a medium-sized
gullGulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
which breeds in northern
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, northern
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
and northwestern
North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
. It
migratesBird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. These however are usually irregular or in only one direction and are termed variously as nomadism, invasions,...
further south in winter. Its name does not indicate that it is an abundant species, but that during the winter it feeds on
common landCommon land is land owned collectively or by one person, but over which other people have certain traditional rights, such as to allow their livestock to graze upon it, to collect firewood, or to cut turf for fuel. By extension, the term "commons" has come to be applied to other resources which a...
, short pasture used for grazing.
Adults are 40-46 cm long, obviously smaller than the
Herring GullThe Herring Gull, Larus argentatus, is a large gull , and is the most abundant and best known of all gulls along the shores of Asia, western Europe, and North America. It breeds across North America, Europe and Asia...
, and slightly smaller than the
Ring-billed GullThe Ring-billed Gull is a medium-sized gull.Adults are length and with a wingspan. They have a white head, neck and underparts and a relatively short, yellow bill with a dark ring. The back and wings are silver grey and they have yellow legs. Their eyes are yellow and their outer rims are red...
, also differing from this in its shorter, more tapered bill with a more greenish shade of yellow, as well as being unmarked during the breeding season.
The
Common Gull,
Mew Gull or
Sea Mew (
Larus canus) is a medium-sized
gullGulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
which breeds in northern
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, northern
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
and northwestern
North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
. It
migratesBird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. These however are usually irregular or in only one direction and are termed variously as nomadism, invasions,...
further south in winter. Its name does not indicate that it is an abundant species, but that during the winter it feeds on
common landCommon land is land owned collectively or by one person, but over which other people have certain traditional rights, such as to allow their livestock to graze upon it, to collect firewood, or to cut turf for fuel. By extension, the term "commons" has come to be applied to other resources which a...
, short pasture used for grazing.
Adults are 40-46 cm long, obviously smaller than the
Herring GullThe Herring Gull, Larus argentatus, is a large gull , and is the most abundant and best known of all gulls along the shores of Asia, western Europe, and North America. It breeds across North America, Europe and Asia...
, and slightly smaller than the
Ring-billed GullThe Ring-billed Gull is a medium-sized gull.Adults are length and with a wingspan. They have a white head, neck and underparts and a relatively short, yellow bill with a dark ring. The back and wings are silver grey and they have yellow legs. Their eyes are yellow and their outer rims are red...
, also differing from this in its shorter, more tapered bill with a more greenish shade of yellow, as well as being unmarked during the breeding season. The body is grey above and white below. The legs are greenish-yellow. In winter, the head is streaked grey, and the bill often has a poorly-defined blackish band near the tip (sometimes sufficiently obvious to cause confusion with Ring-billed Gull). They have black wingtips with large white "mirrors". Young birds have scaly black-brown upperparts and a neat wing pattern, and grey legs. They take two to three years to reach maturity. The call is a high-pitched "laughing" cry.
Taxonomy
There are four
subspeciesSubspecies in biological classification, is 1) a taxonomic rank subordinate to species, or 2) a taxonomic unit, a taxon in that rank...
, two of them considered distinct species by some authorities:
- Larus canus canus Linnaeus, 1758. Common Gull. Europe and western Asia. Small; mantle medium grey (palest subspecies); wingtips with extensive black; iris dark. Wingspan 110-125 cm; weight 290-480 g.
- Larus canus heinei Homeyer, 1853. Central northern Asia. Medium size; mantle dark grey (darkest subspecies); wingtips with extensive black; iris dark. Weight 315-550 g.
- Larus canus kamtschatschensis (Bonaparte, 1857); syn. L. kamtschatschensis. "Kamchatka Gull". Northeastern Asia. Large; mantle medium-dark grey; wingtips with extensive black; iris pale. Weight 394-586 g.
- Larus canus brachyrhynchus Richardson, 1831; syn. L. brachyrhynchus. Mew Gull or "Short-billed Gull". Alaska
Alaska is the largest state of the United States of America by area; it is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
and western CanadaCanada is a country occupying most of northern North America, extending from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean...
. Small; mantle medium-dark grey; wingtips with little black and much white; iris pale. Wingspan 96-102 cm; weight 320-550 g.
Ecology
Both Common and Mew Gulls breed colonially near water or in marshes, making a lined nest on the ground or in a small tree;
colony sizeMany animals, including humans, tend to live in groups, herds, flocks, bands, packs, shoals, or colonies of conspecific individuals. The size of these groups, as expressed by the number of participant individuals, is an important aspect of their social environment...
varies from 2 to 320 or even more pairs. Usually three eggs are laid (sometimes just one or two); they hatch after 24–26 days, with the chicks fledging after a further 30–35 days. Like most gulls, they are omnivores and will scavenge as well as hunt small prey. The global population is estimated to be about one million pairs; they are most numerous in Europe, with over half (possibly as much as 80-90%) of the world population. By contrast, the Alaskan population is only about 10,000 pairs.
Vagrancy
The Common Gull occurs as a scarce winter visitor to coastal eastern Canada and as a vagrant to the northeastern
USAThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, and there is one recent record of Mew Gull in Europe on the
AzoresThe Azores is a Portuguese archipelago in the Atlantic Ocean, about from Lisbon and about from the east coast of North America. The two westernmost Azorean islands actually lie on the North American plate...
.
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