Caspian Gull
Encyclopedia
Caspian Gull is a name applied to the gull
taxon
Larus (argentatus) cachinnans, a member of the Herring Gull/Lesser Black-backed Gull
complex.
. The eye is small and often dark, 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.
and Caspian Sea
s, extending eastwards across Central Asia
to north-west China
. In Europe
it has been spreading north and west and now breeds in Poland
and eastern Germany
. 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. Small numbers are now seen regularly in Britain
, especially in South-east England, East Anglia
and the Midlands
.
s and predators with a very varied diet. During the breeding season they often eat rodent
s such as ground squirrel
s, flying some distance into the steppes to find them.
Records Committee). Some authorities include the Yellow-legged Gull (L. michahellis) within L. cachinnans but it is 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 non-breeding range is still little-known but most are thought to winter in south-west Asia
from the Persian Gulf to north-west 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 East Siberian Gull
or as a species in its own right. It breeds in Mongolia
and surrounding areas and migrates south-east in winter.
Gull
Gulls 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...
taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
Larus (argentatus) cachinnans, a member of the Herring Gull/Lesser Black-backed Gull
Lesser Black-backed Gull
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...
complex.
Description
It is a large gull at 59 – and a body mass of 680 –. with a long, slender bill, ccentuated by the sloping forehead. The legs, wings and neck are longer than those of the Herring Gull and Yellow-legged GullYellow-legged Gull
The Yellow-legged Gull , sometimes referred to as Western Yellow-legged Gull , is a large gull of Europe, the Middle East and North Africa, which has only recently achieved wide recognition as a distinct species...
. The eye is small and often dark, 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.
Distribution
The Caspian Gull breeds around the BlackBlack Sea
The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...
and Caspian Sea
Caspian Sea
The Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the world's largest lake or a full-fledged sea. The sea has a surface area of and a volume of...
s, extending eastwards across Central Asia
Central Asia
Central Asia is a core region of the Asian continent from the Caspian Sea in the west, China in the east, Afghanistan in the south, and Russia in the north...
to north-west China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. In Europe
Europe
Europe 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 watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
it has been spreading north and west and now breeds in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
and eastern Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
. Some birds migrate south as far as the Red Sea
Red Sea
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...
and Persian Gulf
Persian Gulf
The Persian Gulf, in Southwest Asia, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.The Persian Gulf was the focus of the 1980–1988 Iran-Iraq War, in which each side attacked the other's oil tankers...
while others disperse into Western Europe
Western Europe
Western Europe is a loose term for the collection of countries in the western most region of the European continents, though this definition is context-dependent and carries cultural and political connotations. One definition describes Western Europe as a geographic entity—the region lying in the...
, in countries such as Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, Norway and Denmark. Small numbers are now seen regularly in Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
, especially in South-east England, East Anglia
East Anglia
East Anglia is a traditional name for a region of eastern England, named after an ancient Anglo-Saxon kingdom, the Kingdom of the East Angles. The Angles took their name from their homeland Angeln, in northern Germany. East Anglia initially consisted of Norfolk and Suffolk, but upon the marriage of...
and the Midlands
English Midlands
The Midlands, or the English Midlands, is the traditional name for the area comprising central England that broadly corresponds to the early medieval Kingdom of Mercia. It borders Southern England, Northern England, East Anglia and Wales. Its largest city is Birmingham, and it was an important...
.
Breeding
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.Feeding
They are scavengerScavenger
Scavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out dead animal and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by...
s and predators with a very varied diet. During the breeding season they often eat rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s such as ground squirrel
Ground squirrel
The ground squirrels are members of the squirrel family of rodents which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known as marmots or prairie dogs, while the smaller and less...
s, flying some distance into the steppes to find them.
Classification and subspecies
This form has a troubled taxonomic history, summarised in the Herring Gull article. Currently, it is treated as a full species by some authorities and as a subspecies of the Herring Gull by others (e.g. the British Ornithologists' UnionBritish Ornithologists' Union
The British Ornithologists' Union aims to encourage the study of birds in Britain, Europe and elsewhere, in order to understand their biology and to aid their conservation....
Records Committee). Some authorities include the Yellow-legged Gull (L. michahellis) within L. cachinnans but it is 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
Heuglin's Gull
Heuglin's Gull or Siberian Gull, Larus heuglini, is a seabird in the genus Larus. It is closely related to the Lesser Black-backed Gull, Larus fuscus, and is often classified as a subspecies of it...
. The Steppe Gull breeds in Central Asia, particularly northern Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
. Its non-breeding range is still little-known but most are thought to winter in south-west Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
from the Persian Gulf to north-west India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. There are possible records of this form from Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...
and South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...
.
The Mongolian Gull (L. (vegae/cachinnans) mongolicus) may be classed as a subspecies of the Caspian Gull, a subspecies of the East Siberian Gull
East Siberian Gull
The Vega Gull or East Siberian Gull, Larus vegae, is a large gull of the Herring Gull/Lesser Black-backed Gull complex which breeds in North-east Asia. Its classification is still controversial and uncertain. It is variously treated as a separate species, as a subspecies of American Herring Gull...
or as a species in its own right. It breeds in Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
and surrounding areas and migrates south-east in winter.
Identification
- Garner & Quinn, British Birds 90:25-63, 369-84
- Bakker, Theo, Rudy Offereins and Rik Winters (2000) Caspian Gull identification gallery, Birding WorldBirding WorldBirding World is a monthly birding magazine published in the United Kingdom. It is the magazine of the Bird Information Service, based at Cley next the Sea, Norfolk....
13(2): 60-74 (identification article including 34 images of Caspian Gulls of various ages) - Neubauer, Gregory & Richard Millington (2000) Caspian Gull identification revisited Birding WorldBirding WorldBirding World is a monthly birding magazine published in the United Kingdom. It is the magazine of the Bird Information Service, based at Cley next the Sea, Norfolk....
13(11): 462-5 (addresses identification in juvenile plumage) - Small, Brian (2001) The juvenile Caspian Gull in Suffolk Birding WorldBirding WorldBirding World is a monthly birding magazine published in the United Kingdom. It is the magazine of the Bird Information Service, based at Cley next the Sea, Norfolk....
14(9): 385-7 - Gibbins, Chris, Brian J. Small and John Sweeney (2010) From the Rarities Committee's files: Identification of Caspian Gull, part 1: typical birds British BirdsBritish Birds (magazine)British Birds is a monthly ornithology magazine that was established in 1907. It is now published by BB 2000 Ltd, which is wholly owned by The British Birds Charitable Trust , established for the benefit of British ornithology...
103(3): 142-183 (detailed identification paper, covering typical individuals)
External links
- Caspian Gull photos, Rudy's Gull-index
- Gulls in Poland incl. Caspian Gull and hybrids
- Caspian Gulls in Amsterdam
- Identification of Caspian Gull, Berkshire Birds
- Steppe Gull barabensis in South Korea, Birds Korea
- Pictures of Caspain Gulls from all ages included some hybrids and ringed Caspian Gulls