- Source: Common gull
The common gull (Larus canus) is a medium-sized gull that breeds in cool temperate regions of the Palearctic from Iceland and Scotland east to Kamchatka in the Russian Far East. Most common gulls migrate further south in winter, reaching the Mediterranean Sea, the southern Caspian Sea, and the seas around China and Japan; northwest European populations are at least partly resident. The closely related short-billed gull was formerly often included in this species, which was then sometimes known collectively as "mew gull".
Taxonomy
The common gull was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the current binomial name Larus canus. Linnaeus specified the type locality as Europe but this is now restricted to Sweden. The genus name is a Latin word for a seabird, probably a gull. The specific epithet canus is also Latin and means "grey". The name "common gull" was coined by Thomas Pennant in 1768 because he considered it the most numerous of its genus. John Ray earlier used the name common sea-mall.
There are many old British regional names for this species, typically variations on maa, mar, and mew. The original English word mew is related to German möwe and Dutch meeuw, and is ultimately onomatopoeic. In Norse influenced regions of Britain, variations include maw or sea-maw, the old Norfolk form being mow. The word gull comes from a Celtic root, with the first recorded usage in English from the 1400s; the modern Welsh form is gwylan.
= Subspecies
=There are three subspecies, with the Kamchatka gull (L. (c.) kamtschatschensis) being considered a potential distinct species by some authorities.
The North American short-billed gull was formerly widely considered conspecific with this species (as Larus canus brachyrhynchus), but most authorities now accept it as a distinct species L. brachyrhynchus, based on differences in genetics, morphology and calls. Though the name "mew gull" was then widely used outside of North America as its unique subspecific name, this name was also used in North America for Larus canus as a whole, so the name "short-billed gull" was chosen for L. brachyrhynchus by the American Ornithological Society (AOS) to avoid confusion with this North American usage of mew gull to denote all forms of the L. canus complex. The revival of the name short-billed gull in some of the same literature for L. brachyrhynchus, and that that short-billed gull was used historically for L. brachyrhynchus when it was treated as a distinct species in the first to third editions of the AOU (now AOS) checklist (in which the name mew gull, contrary to more recent usage, was specifically reserved for the Old World subspecies).
Description
Adult common gulls are 40–46 cm (16–18 in) long and a wingspan of 100–115 cm (39–45 in), noticeably smaller than the herring gull and slightly smaller than the ring-billed gull. It is further distinguished from the ring-billed gull by its shorter, more tapered bill, which is a more greenish shade of yellow and is unmarked during the breeding season. The body is grey above and white below. The legs are yellow in breeding season, becoming duller in the winter. In winter, the head is streaked grey and the bill often has a poorly defined blackish band near the tip, which is sometimes sufficiently obvious to cause confusion with ring-billed gull. They have black wingtips with large white "mirrors" on the outer primaries p9 and p10, which are smaller than those in the short-billed gull. Young birds have scaly black-brown upperparts and a neat wing pattern, and pink legs which become greyish in the second year before tuning yellow. By the first winter, the head and belly are white, with fine streaks and greyish feathers grow on the saddle. They take three years (up to four in the Kamchatka subspecies) to reach maturity. The call is a high-pitched "laughing" cry.
Distribution
The common gull breeds in the northern Palearctic from Iceland eastwards to northeast Siberia. It is mainly migratory and winters in Europe, the Mediterranean, Black and Caspian seas, Persian Gulf; Sea of Okhotsk, Japan, Korean Peninsula to southeast China.
It occurs as a scarce winter visitor to coastal eastern Canada and as a vagrant to the northeastern USA. The Kamchatka gull is occasionally seen in northwestern North America mainly in spring, and there is one autumn record in Newfoundland.
Behaviour and ecology
= Breeding
=The common gull usually breeds colonially, but can be solitary. Both sexes make a lined nest on the ground or in a small tree near water or in marshes. Usually three eggs are laid (sometimes just one or two). They are incubated by both parents and hatch after 24–26 days. The chicks are precocial but remain in the vicinity of the nest. They are cared for by both parents and fledge when aged around 35 days.
= Food and feeding
=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 short-billed gull population in Alaska is only about 10,000 pairs.
References
Sources
External links
BirdLife species factsheet for Larus canus
"Larus canus". Avibase.
"Mew Gull media". Internet Bird Collection.
Mew Gull photo gallery at VIREO (Drexel University)
Interactive range map of Larus canus at IUCN Red List maps
Audio recordings of Mew gull on Xeno-canto.
Larus canus in Field Guide: Birds of the World on Flickr
Common gull media from ARKive
Kata Kunci Pencarian:
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- Yoichi, Hokkaido
- Setana, Hokkaido
- Common gull
- Gull
- Black-headed gull
- Silver gull
- Great black-backed gull
- Pacific gull
- Ring-billed gull
- Lesser black-backed gull
- Caspian gull
- Yellow-legged gull