great skua

The great skua was described from the Faroe Islands and Iceland by the Danish zoologist Morten Thrane Brünnich in 1764 under the binomial name Catharacta skua.{{ cite book | last=Brünnich | first=Morten Thrane | author-link=Morten Thrane Brünnich | year=1764 | title=M. Th. Brünnichii Ornithologia borealis, sistens collectionem avium : ex omnibus, Imperio danico subjectis, provinciis insulisqve borealibus Hafniæ factam, cum descriptionibus novarum, nominibus incolarum, locis natalium et icone | language=Latin | location=Hafniae [Copenhagen] | publisher=Typis Andreæ Hartvigii Godiche | pages=33–36 | url=https://www.biodiversitylibrary.org/page/57974732 }}{{ cite book | editor-last=Peters | editor-first=James Lee | editor-link=James L. Peters | year=1934 | title=Check-List of Birds of the World | volume=2 | publisher=Harvard University Press | place=Cambridge, Massachusetts | pages=309–310 | url=https://www.biodiversitylibrary.org/page/14483122 }} It is now placed in the genus Stercorarius that was introduced by the French zoologist Mathurin Jacques Brisson in 1760.{{ cite book | last=Brisson | first=Mathurin Jacques | author-link=Mathurin Jacques Brisson | year=1760 | title=Ornithologie, ou, Méthode Contenant la Division des Oiseaux en Ordres, Sections, Genres, Especes & leurs Variétés | language=French, Latin | at=[https://biodiversitylibrary.org/page/36010456 Vol. 1, p. 56], [https://biodiversitylibrary.org/page/36210999 Vol. 6, p. 149] | place=Paris | publisher=Jean-Baptiste Bauche }}{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | editor3-last=Rasmussen | editor3-first=Pamela | editor3-link=Pamela Rasmussen | year=2020 | title=Noddies, gulls, terns, auks | work=IOC World Bird List Version 10.1 | url=https://www.worldbirdnames.org/bow/gulls/ | publisher=International Ornithologists' Union | access-date=4 June 2020 }} The English name and species name "skua" is believed to originate from the Faroese {{Lang|fao|skúvur}} or {{Lang|fao|skúgvur}} {{IPA|fo|ˈskɪkvʊər|}} and is the only known bird name to originate from the Faroes that has come into regular use elsewhere.{{Cite OED |Skua}} In Britain, it is sometimes known by the name bonxie, a Shetland name of Norse origin.{{citation |title=English Review Magazine|url=https://books.google.com/books?id=GeUvAAAAMAAJ|volume=2-3|year=1949|publisher=Eyre and Spottiswoode limited.|page=369}} The genus name Stercorarius is Latin and means "of dung"; the food disgorged by other birds when pursued by skuas was once thought to be excrement.{{cite book | last= Jobling | first= James A | year= 2010| title= The Helm Dictionary of Scientific Bird Names | url= https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling | publisher= Christopher Helm | location = London | isbn = 978-1-4081-2501-4 | page=[https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling/page/n365 365]}} The species is monotypic: no subspecies are recognised.

File:Stercorarius skua collage, Runde, Norway 06-06.jpg

Great skuas measure {{convert|50|–|58|cm|in|abbr=on}} long and have a {{convert|125|–|140|cm|in|abbr=on}} wingspan. One study found that 112 males weighed an average of {{convert|1.27|kg|lboz|abbr=on}} and that 125 females weighed an average of {{convert|1.41|kg|lboz|abbr=on}}. Adults are a streaked greyish brown, with a black cap, while juveniles are a warmer brown and unstreaked below. They have a short, blunt tail, and a powerful flight. The great skua's call is a harsh hah-hah-hah-hah; quacking and croaking noises have also been heard. Distinguishing this skua from the other North Atlantic skuas (parasitic jaeger, pomarine jaeger and long-tailed jaeger) is relatively straightforward. The herring gull size, massive barrel chest and white wing flashes of this bird are distinctive even at a distance. It is sometimes said to give the impression of a common buzzard. Identification of this skua is only complicated when it is necessary to distinguish it from the closely related large southern-hemisphere skuas. Despite its name, the great skua is marginally smaller on average than the other 3 large southern-hemisphere skuas, although not by enough to distinguish them by size in the field. Some authorities still regard the great skua as conspecific with some of these southern skuas, and as a group they have sometimes been separated in the genus Catharacta, although currently this taxonomy is not commonly followed.

File:Storkjove.1.jpg)]]

Genetic studies have found surprising similarities between the great skua and the pomarine skua, despite their dissimilar appearance. Many ornithologists now believe either that the great skua originated as a hybrid between the pomarine skua and one of the southern-hemisphere species, presumably as a result of vagrancy or migration across the equator by the southern species, or that the pomarine skua evolved from hybridization of the great skua and one of the small Arctic species (see pomarine jaeger for details).

File:Stercorarius skua MWNH 0302.JPG]]

The great skua breeds in Iceland, Norway, the Faroe Islands, and on Scottish islands, with some individuals breeding on mainland Scotland and in the northwest of Ireland. They breed on coastal moorland and rocky islands, usually laying two spotted olive-brown eggs in grass-lined nests. Like other skuas, they will fly at the head of a human or other intruder approaching their nest. Although it cannot inflict serious damage, such an experience with a bird of this size is frightening. They are a migrant species, wintering at sea in the Atlantic Ocean and regularly reaching North American waters. They are vagrant to Mediterranean countries (e.g. Turkey).

They eat mainly fish, birds, eggs, carrion, offal, rodents, rabbits, and occasionally berries. They have been known to prey on lambs, and even pony foals. Probably their most prolific food source is by-catch abandoned by fishing vessels.{{cite web | url=https://www.bbc.com/travel/article/20211208-foula-britains-most-remote-inhabited-island | title=Foula: Britain's most remote inhabited island }}

File:Great Skua attacking Gannet near Stac an Armin.jpg near Stac an Armin (St Kilda, Scotland)]]

They will often obtain fish by robbing gulls, terns and even northern gannets of their catches. They will also directly attack and kill other seabirds, up to the size of herring gulls. Like most other skua species, it continues this piratical behaviour throughout the year, showing less agility and more brute force than the smaller skuas when it harasses its victims. A common technique is to fly up to a gannet in mid-air and grab it by the wing, so that it stalls and falls into the sea, where the great skua then physically attacks it until it surrenders its catch. Due to its size, aggressive nature and fierce defence of its nest, the great skua has little to fear from other predators. While fledglings can fall prey to rats, cats or the Arctic fox, healthy adults are threatened only by greater raptors such as the golden eagle, the white-tailed eagle, and more rarely, at sea by the orca.

An aerial apex predator, the great skua is an also an aggressive kleptoparasite, deliberately harassing birds as large as gannets to steal a free meal. It also readily kills and eats smaller birds such as puffins. Great skuas show little to no fear of humans – anybody getting close to the nest will be repeatedly dive-bombed by the territorial adults.

Unusual behaviour by St Kilda's skuas was recorded in 2007 during research into recent falls in the Leach's storm petrel population. Using night vision gear, ecologists observed the skuas preying on the petrels at night, a remarkable strategy for a seabird.

File:GreatSkuaInWater.jpg|Great skua in water

File:Skua_Runde.jpg|At the Norwegian bird island Runde

File:Skua_Runde2.jpg|At Runde

File:Great skua (Stercorarius skua), Hallig Hooge.jpg|Great skua at North Sea island Hallig Hooge / Germany

File:Große Raubmöwe (Stercorarius skua) auf Handa Island.JPG|At Handa Island / Scotland

Stercorarius skua MHNT.ZOO.2010.11.139.8.jpg |Museum specimen

{{Reflist|refs=

{{cite web |first=Steven |last=McKenzie |url=http://news.bbc.co.uk/1/hi/scotland/highlands_and_islands/7069755.stm |title=Bird night attacks may be unique |date=5 November 2007 |publisher=BBC News |access-date=6 November 2007}}

{{cite book |title=CRC Handbook of Avian Body Masses |editor-first=John B. Jr. |editor-last=Dunning |publisher=CRC Press |year=2008 |isbn=978-1-4200-6444-5}}

{{cite book |last1=Furness |first1=Robert W. |first2=Keith |last2=Hamer |year=2003 |title=Firefly Encyclopedia of Birds |chapter=Skuas and Jaegers |editor-first=Christopher |editor-last=Perrins |editor-link=Christopher Perrins |pages=[https://archive.org/details/fireflyencyclope0000unse/page/270 270–273] |publisher=Firefly Books |isbn=1-55297-777-3 |chapter-url-access=registration |chapter-url=https://archive.org/details/fireflyencyclope0000unse/page/270 }}

{{cite journal |last=Salomonsen |first=F. |year=1935 |title=Den færøiske ornithologis historie indtil aar 1800 supplement |journal=Dansk Ornithologisk Forenings Tidsskrift |pages=67–100 |language=da}}

{{cite web |title=Dictionary of the Scots Language |url=http://www.dsl.ac.uk/entry/snd/bonxie}}

}}

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• {{cite book |last1=Bull |first1=John |last2=Farrand Jr. |first2=John |title=The Audubon Society Field Guide to North American Birds, Eastern Region |date=April 1984 |publisher=Alfred A. Knopf |location=New York |isbn=0-394-41405-5 |url-access=registration |url=https://archive.org/details/audubonsocietyfi0000bull }}

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{{Commons category|Stercorarius skua}}

{{Wikispecies|Stercorarius skua}}

• {{usurped|1=[https://web.archive.org/web/20210226100207/http://www.handaskuas.org/ More great skua information and photos]}} at the Handa Island Skua Project
• {{BirdLife|22694160|Catharacta skua}}
• {{Avibase|name=Stercorarius skua}}
• {{EBirdSpecies|gresku1|Great Skua}}
• {{VIREO|great+skua}}
• {{IUCN_Map|22694160/166269759|Catharacta skua}}
• {{Xeno-canto species|Stercorarius|skua|Great skua}}
• {{field guide birds of the world|Stercorarius skua}}
• {{ARKive}}

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great skua

Category:Birds of the Arctic

Category:Birds of Iceland

Category:Birds of Scandinavia

Category:Birds of the Atlantic Ocean

great skua

Category:Taxa named by Morten Thrane Brünnich

Category:Taxobox binomials not recognized by IUCN

Category:Apex predators