Big Koniuji Black-legged Kittiwake colony

The kittiwakes (

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

''Rissa'') are two closely related

seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...

species in the

gull Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century ...

family Laridae, the black-legged kittiwake (''Rissa tridactyla'') and the

red-legged kittiwake The red-legged kittiwake (''Rissa brevirostris'') is a seabird species in the gull family Laridae. It breeds in the Pribilof Islands, Bogoslof Island and Buldir Island in the Bering Sea off the coast of Alaska, and the Commander Islands, Russia ...

(''Rissa brevirostris''). The epithets "black-legged" and "red-legged" are used to distinguish the two species in North America, but in Europe, where ''Rissa brevirostris'' is not found, the black-legged kittiwake is often known simply as kittiwake, or more colloquially in some areas as tickleass or tickleace. The name is derived from its call, a shrill 'kittee-wa-aaake, kitte-wa-aaake'. The genus name ''Rissa'' is from the Icelandic name ''Rita'' for the black-legged kittiwake.

Description

The two species are indeed physically very similar. They have a white head and body, grey back, grey wings tipped solid black and a bright yellow bill. Black-legged kittiwake adults are somewhat larger (roughly in length with a wingspan of ) than red-legged kittiwakes ( in length with a wingspan around ). Other differences include a shorter bill, larger eyes, a larger, rounder head and darker grey wings in the red-legged kittiwake. While most black-legged kittiwakes do, indeed, have dark-grey legs, some have pinkish-grey to reddish legs, making colouration a somewhat unreliable identifying marker. In contrast to the dappled chicks of other gull species, kittiwake chicks are downy and white since they are under relatively little threat of predation, as the nests are on extremely steep cliffs. Unlike other gull chicks which wander around as soon as they can walk, kittiwake chicks instinctively sit still in the nest to avoid falling off. Juveniles take three years to reach maturity. When in winter plumage, both birds have a dark grey smudge behind the eye and a grey hind-neck collar. The sexes are visually indistinguishable.

Distribution and habitat

Kittiwakes are coastal breeding birds ranging in the

North Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

, North Atlantic, and

Arctic The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...

oceans. They form large, dense, noisy

colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...

during the summer reproductive period, often sharing habitat with

murres ''Uria'' is a genus of seabirds in the auk family known in Britain as guillemots, in most of North America as murres, and in Newfoundland and Labrador as turr. These are medium-sized birds with mainly brown or black plumage in the breeding s ...

. They are the only gull species that are exclusively cliff-nesting. A colony of kittiwakes living in

Newcastle upon Tyne Newcastle upon Tyne ( RP: , ), or simply Newcastle, is a city and metropolitan borough in Tyne and Wear, England. The city is located on the River Tyne's northern bank and forms the largest part of the Tyneside built-up area. Newcastle is ...

and Gateshead in the north east of England has made homes on both the

Tyne Bridge The Tyne Bridge is a through arch bridge over the River Tyne in North East England, linking Newcastle upon Tyne and Gateshead. The bridge was designed by the engineering firm Mott, Hay and Anderson, who later designed the Forth Road Bridge, ...

and Baltic Centre for Contemporary Art. This colony is notable because it is the furthest inland colony of kittiwakes in the world.

Species

Photo gallery

File:Kittiwake w.jpg, Kittiwake – winter

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

File:Kittiwake with young chick.jpg, Kittiwake with chicks,

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...

File:Rissa tridactyla -Staple Island, Farne Islands, Northumberland, England -adult and chicks-8.jpg,

Farne Islands The Farne Islands are a group of islands off the coast of Northumberland, England. The group has between 15 and 20 islands depending on the level of the tide.

, England

References

External links

{{Taxonbar, from=Q310848 Kittiwakes Taxa named by James Francis Stephens