Caspian gull | |
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Adult in summer plumage, Romania | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Laridae |
Genus: | Larus |
Species: | L. cachinnans |
Binomial name | |
Larus cachinnans Pallas, 1811 | |
Range of L. cachinnans Breeding Resident Non-breeding |
The Caspian gull (Larus cachinnans) is a large gull and a member of the herring and lesser black-backed gull complex. The scientific name is from Latin. Larus appears to have referred to a gull or other large seabird, and cachinnans means 'laughing', from cachinnare 'to laugh'. [2]
It is a large gull at 56–68 cm (22–27 in) long, with a 137 to 155 cm (54 to 61 in) wingspan and a body mass of 680–1,590 g (1.50–3.51 lb). [3] [4] Among standard measurements, the wing chord is 38.5 to 48 cm (15.2 to 18.9 in), the bill is 4.6 to 6.4 cm (1.8 to 2.5 in) and the tarsus is 5.8 to 7.7 cm (2.3 to 3.0 in). [4] The Caspian gull has a long, slender bill, accentuated by the sloping forehead. The legs, wings, and neck are longer than those of the herring gull and yellow-legged gull. The eye is small and often dark, and the legs vary from pale pink to a pale yellowish colour. The back and wings are a slightly darker shade of grey than the herring gull, but slightly paler than the yellow-legged gull. The outermost primary feather has a large white tip and a white tongue running up the inner web.
First-winter birds have a pale head with dark streaking on the back of the neck. The underparts are pale and the back is greyish. The greater and median wing coverts have whitish tips forming two pale lines across the wing.
The Caspian gull breeds around the Black and Caspian Seas, extending eastwards across Central Asia to north-west China. In Europe, it has been spreading north and west and now breeds in Poland, eastern Germany, southern Russia and all year round in Ukraine. Some birds migrate south as far as the Red Sea and Persian Gulf, while others disperse into Western Europe, in countries such as Sweden, Norway and Denmark or the Benelux and even North of France. Small numbers are now seen regularly in Britain, especially in South-east England, East Anglia, and the Midlands.
It typically nests on flat, low-lying ground by water, unlike the yellow-legged gull, which mainly nests on cliffs in areas where the two overlap. The breeding season starts from early April. Two or three eggs are laid and incubated for 27 to 31 days.
They are scavengers and predators with a very varied diet. During the breeding season, they often eat rodents such as ground squirrels, flying some distance into the steppes to find them.
This form has a troubled taxonomic history, summarised in the herring gull article. The Caspian gull used to be treated as a subspecies of the herring gull, but it is now treated as a full species by many authorities (e.g. the British Ornithologists' Union records committee). Some authorities include the yellow-legged gull (L. michahellis) within L. cachinnans, but it is also now commonly considered to be a separate species.
The steppe gull or Baraba gull (L. (cachinnans) barabensis) may be regarded as a subspecies of the Caspian gull or as a separate species. It is also very similar genetically to its northern neighbour, the taimyrensis race of Heuglin's gull. The steppe gull breeds in Central Asia, particularly northern Kazakhstan. Its nonbreeding range is still little-known, but most are thought to winter in southwestern Asia from the Persian Gulf to northwestern India. There are possible records of this form from Hong Kong and South Korea.
The Mongolian gull (L. (vegae/cachinnans) mongolicus) may be classed as a subspecies of the Caspian gull, a subspecies of the Vega gull, or as a species in its own right. It breeds in Mongolia and the surrounding areas and migrates southeast in winter.
The common gull or sea mew is a medium-sized gull that breeds in the Palearctic. The closely related short-billed gull is sometimes included in this species, which may be known collectively as "mew gull". Many common gulls migrate further south in winter.
The laughing gull is a medium-sized gull of North and South America. Named for its laugh-like call, it is an opportunistic omnivore and scavenger. It breeds in large colonies mostly along the Atlantic coast of North America, the Caribbean, and northern South America. The two subspecies are L. a. megalopterus — which can be seen from southeast Canada down to Central America — and L. a. atricilla, which appears from the West Indies to the Venezuelan islands. The laughing gull was long placed in the genus Larus until its present placement in Leucophaeus.
The European herring gull is a large gull, up to 66 cm (26 in) long. It breeds throughout the northern and western coasts of Europe. Some European herring gulls, especially those resident in colder areas, migrate further south in winter, but many are permanent residents, such as in Ireland, Britain, Iceland, or on the North Sea shores. They have a varied diet, including fish, crustaceans, as well as some plants, and are also scavengers, consuming carrion and food left by or stolen from humans.
The lesser black-backed gull is a large gull that breeds on the Atlantic coasts of Europe. It is migratory, wintering from the British Isles south to West Africa. However, it has increased dramatically in North America, especially along the east coast. Formerly just a winter visitor to North America, it has increased and occurs in large numbers some winters and birds are now recorded year-round. However, there is serious concern about decline in many parts of its range. The species is on the UK Amber List because the UK is home to 40 per cent of the European population and more than half of these are found at fewer than ten breeding sites.
The glaucous gull is a large gull, the second-largest gull in the world. The genus name is from Latin larus, which appears to have referred to a gull or other large seabird. The specific name hyperboreus is Latin for "northern" from the Ancient Greek Huperboreoi people from the far north "Glaucous" is from Latin glaucus and denotes the grey colour of the gull. An older English name for this species is burgomaster.
The Iceland gull is a medium-sized gull that breeds in the Arctic regions of Canada and Greenland, but not in Iceland, where it is only seen during winter. The genus name is from Latin larus, which appears to have referred to a gull or other large seabird. The specific name glaucoides denotes its resemblance to Larus glaucus, a synonym of Larus hyperboreus, the glaucous gull; -oides is Ancient Greek and means "resembling".
Pallas's gull, also known as the great black-headed gull, is a large bird species. As is the case with many gulls, it has traditionally been placed in the genus Larus. The scientific name is from Ancient Greek. Ichthyaetus is from ikhthus, "fish", and aetos, "eagle".
The yellow-legged gull is a large gull found in Europe, the Middle East and North Africa, which has only recently achieved wide recognition as a distinct species. It was formerly treated as a subspecies of either the Caspian gull L. cachinnans, or more broadly as a subspecies of the herring gull L. argentatus. The genus name is from Latin Larus which appears to have referred to a gull or other large seabird, and the species name honours the German zoologist Karl Michahelles.
The California gull is a medium-sized gull, smaller on average than the herring gull, but larger on average than the ring-billed gull. It lives not just in California, but up and down the entire Western coast of North America, and has breeding ground inland. The yellow bill has a black ring.
The kelp gull, also known as the Dominican gull, is a gull that breeds on coasts and islands through much of the Southern Hemisphere. The nominate L. d. dominicanus is the subspecies found around South America, parts of Australia, and New Zealand. L. d. vetula is a subspecies occurring around Southern Africa.
The slaty-backed gull is a large, white-headed gull that breeds on the north-eastern coast of the Palearctic, but travels widely during nonbreeding seasons. It is similar in appearance to the western gull and the glaucous-winged gull. Another alternate name is Pacific gull, though it also applies to a Southern Hemisphere species, L. pacificus.
The glaucous-winged gull 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 Neo-Latin for "glaucous" from the Ancient Greek, glaukos, denoting the grey color of its wings.
Gulls of Europe, Asia and North America by Klaus Malling Olsen and Hans Larsson is a volume in the Helm Identification Guides series of bird identification books.
Thayer's gull is a subspecies of the Iceland gull. It is a large gull native to North America.
Heuglin's gull or the Siberian gull, is a seabird in the genus Larus.
The Armenian gull is a large gull found in the Caucasus and the Middle East. It was formerly classified as a subspecies of the European herring gull, but is now generally considered to be a separate species, although BirdLife International lumps it with the yellow-legged gull.
The Vega gull, East Siberian gull, or East Siberian herring gull is a large gull of the herring gull/lesser black-backed gull complex which breeds in Northeast Asia. Its classification is still controversial and uncertain. It is variously treated as a separate species, as a subspecies of the American herring gull or included with both the American herring gull and European herring gull in L. argentatus. The Mongolian gull, Larus mongolicus, has previously been regarded as a subspecies of the Caspian gull but is now sometimes lumped with the Vega gull.
The American herring gull or Smithsonian gull is a large gull that breeds in North America, where it is treated by the American Ornithological Society as a subspecies of herring gull.
Herring gull is a common name for several birds in the genus Larus, all formerly treated as a single species.
The short-billed gull is a medium-sized species of gull that breeds in northwestern North America. In North America, it was previously known as the mew gull, when it was considered conspecific with the palearctic common gull. Most authorities, including the American Ornithological Society in 2021, have split the two populations as distinct species.