The slender-billed gull (''Chroicocephalus genei'') is a mid-sized

gull Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gulls were placed ...

which breeds very locally around the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

and the north of the western

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

(e.g.

Pakistan Pakistan, officially the Islamic Republic of Pakistan, is a country in South Asia. It is the List of countries and dependencies by population, fifth-most populous country, with a population of over 241.5 million, having the Islam by country# ...

) on islands and coastal lagoons. Most of the population is somewhat migratory, wintering further south to as far as North

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

and

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

. A few birds have wandered to western

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

. A

vagrant Vagrancy is the condition of wandering homelessness without regular employment or income. Vagrants usually live in poverty and support themselves by travelling while engaging in begging, scavenging, or petty theft. In Western countries, ...

individual was reportedly seen on

Antigua Antigua ( ; ), also known as Waladli or Wadadli by the local population, is an island in the Lesser Antilles. It is one of the Leeward Islands in the Caribbean region and the most populous island of the country of Antigua and Barbuda. Antigua ...

, April 24, 1976 ( AOU, 2000). The genus name '' Chroicocephalus'' is from

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

''khroizo'', "to colour", and ''kephale'', "head". The specific ''genei'' commemorates Italian naturalist

Giuseppe Gené Carlo Giuseppe Gené (7 December 1800 – 14 July 1847) was an Italian natural history, naturalist and author. Gené was born at Turbigo in Lombardy and studied at the University of Pavia. He published a number of papers on natural history, part ...

Description

This species is long with a wingspan. It is therefore slightly larger than the

black-headed gull The black-headed gull (''Chroicocephalus ridibundus'') is a small gull that breeds in much of the Palearctic in Europe and Asia, and also locally in smaller numbers in coastal eastern Canada. Most of the population is migratory and winters fu ...

, which it resembles, although it does not have a black hood in summer. It has a pale grey body, white head and breast and black tips to the primary wing feathers. The head and dark red bill have an elongated tapering appearance, and this bird also appears long-necked. The legs are dark red, and the iris is yellow. In summer, the breast has a faint pink colouration. This bird takes two years to reach maturity, as is usual in gulls. First year immature birds have a black terminal tail band, and dark areas on the wings. Breeding plumage.jpg, in Breeding plumage, Kutch Larus genei MWNH 0339.JPG, egg Slender-billed gull (Chroicocephalus genei) in flight Sfax.jpg, in flight Slender-billed gulls (Chroicocephalus genei) Cap Bon.jpg, flock

Distribution and habitat

The slender-billed gull breeds in lagoons and lakes around the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

and in similar locations in countries bordering the northwestern part of the

. In 2010 a successful colony was found breeding on an island in a mountain lake in Algeria. The lack of predators and disturbance allowed over 98% of the eggs to hatch. It overwinters on the coast in estuaries and bays. It feeds in deltas, marshes and grassland. It is one of a number of species of gull to feed on landfill sites.

Behaviour

About half of the slender-billed gull's food is fish. It flies a few metres above the surface of the water and dives into the water when it sees suitable

prey Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not ki ...

. It also probes in the mud with its beak to feed on marine invertebrates and catches insects in flight. This rather uncommon gull breeds in

colonies A colony is a territory subject to a form of foreign rule, which rules the territory and its indigenous peoples separated from the foreign rulers, the colonizer, and their '' metropole'' (or "mother country"). This separated rule was often or ...

, nesting on the ground and laying up to three brown-spotted white eggs in a scrape sparsely lined with feathers and bits of vegetation. Incubation takes about 25 days and the young fly after another 25 days. Like most gulls, it is gregarious in winter, both when feeding and in evening roosts. It is not a pelagic species, and is rarely seen far from land.

Status

The slender-billed gull is one of the species to which the ''Agreement on the Conservation of African-Eurasian Migratory Waterbirds'' (

AEWA The Agreement on the Conservation of African-Eurasian Migratory Waterbirds, or African-Eurasian Waterbird Agreement (AEWA), is an independent international treaty developed under the auspices of the United Nations Environment Programme's Convent ...

) applies.

References

{{Taxonbar, from=Q391421 slender-billed gull Birds of Europe Birds of North Africa Birds of Central Asia Birds of West Asia Birds of Pakistan slender-billed gull Taxa named by Ferdinando Arborio Gattinara di Breme