Common Gull | |
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Adult Mew Gull. Anchorage Coastal Wildlife Refuge, Alaska. | |
Conservation status | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Laridae |
Genus: | Larus |
Species: | L. canus |
Binomial name | |
Larus canus Linnaeus, 1758 |
The Common Gull (European and Asian subspecies; see below) or Mew Gull (North American subspecies) Larus canus is a medium-sized gull which breeds in northern Asia, northern Europe and northwestern North America. It migrates further south in winter.[2] Its name does not indicate that it is an abundant species, but that during the winter it feeds on common land, short pasture used for grazing.[3]
Adults are 40-46 cm long, obviously smaller than the Herring Gull, and slightly smaller than the Ring-billed Gull, 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.[2][4]
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There are four subspecies, two of them considered distinct species by some authorities:[2][5]
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 size 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.[6] By contrast, the Alaskan population is only about 10,000 pairs.[2]
The Common Gull occurs as a scarce winter visitor to coastal eastern Canada and as a vagrant to the northeastern USA,[7] and there is one recent record of Mew Gull in Europe on the Azores.[8]
An old historical name for the Common Gull is sea mew,[9] from the old English mǣw.