Difference between revisions of "Pomarine Jaeger" - BirdForum Opus

Latest revision as of 09:45, 11 May 2023

Photo © by postcardcv
Salthouse, Norfolk, England, November 2007

Alternative Name: Pomarine Skua

Stercorarius pomarinus

Identification

53cm including 8cm tail projection of broad twisted streamers

Dark phased
Photo © by IanF North Gare, Seaton Carew, Cleveland, UK, November 2007

Pale Adult

Black cap
Dark upper parts
White underneath with brown breast band and flank bars
White flash on outer wing

Dark Adult all dusky-brown body
Juveniles and immature variably mottled buff/brown

Similar Species

Arctic Skua

Distribution

Far north of Eurasia and North America. It is a migrant, wintering at sea in the tropical oceans.

Taxonomy

This is a monotypic species^[1].

First year bird
Photo © by storensten
Oberkirch, Switzerland, December 2010

Habitat

It nests on arctic tundra and islands

Behaviour

Breeding

It lays 2-3 olive-brown eggs in grass lined depressions.

Diet

Its diet includes lemmings and other rodents on the breeding grounds.

It will also kill birds up to the size of Common Gull.

Vocalisation

References

Clements, JF. 2010. The Clements Checklist of Birds of the World. 6th ed., with updates to December 2010. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/Clements%206.5.xls/view
Wikipedia
Birdwatchers Pocket Guide ISBN 1-85732-804-3
Collins Pocket Guide to British Birds 1966
Collins Field Guid 5th Edition

List of references

Recommended Citation

BirdForum Opus contributors. (2024) Pomarine Jaeger. In: BirdForum, the forum for wild birds and birding. Retrieved 5 May 2024 from https://www.birdforum.net/opus/Pomarine_Jaeger

External Links

Search for photos of Pomarine Jaeger in the gallery

GSearch checked for 2020 platform.1

@@ Line 1: / Line 1: @@
-;Stercorarius pomarinus
+[[Image:Pomskua 121107 0118.jpg|thumb|550px|right|Photo © by {{user|postcardcv|postcardcv}} <br />Salthouse, Norfolk, [[England]], November 2007]]
-[[Image:Pomarine_Jaeger.jpg|thumb|550px|right|Photo by Jacamar]]
+'''Alternative Name: Pomarine Skua'''
-Photographed at No. 63 Beach, Corentyne, Berbice, Guyana
+;[[:Category:Stercorarius|Stercorarius]] pomarinus
-ALSO KNOWN AS POMARINE SKUA
 ==Identification==
-This is a large skua at about 45cm length, excluding the central tail feathers of the summer adult, which can add another 10cm or so. Identification of this skua is complicated by its similarities to Arctic Skua and the existence of three colour phases. Pomarine Skuas are larger than Common Gulls. They are much bulkier, broader-winged and less falcon-like than Arctic Skua, but show the same wide range of plumage variation. The flight is more measured than that of the smaller species.
+cm including 8cm tail projection of broad twisted streamers<br />
+[[Image:Pomarine_Skua.jpg|thumb|350px|right|Dark phased<br />Photo © by {{user|IanF|IanF}} North Gare, Seaton Carew, Cleveland, [[UK]], November 2007]]
-Light-phase adult Pomarine Skuas have a brown back, mainly white underparts and dark primary wing feathers with a white "flash". The head and neck are yellowish-white with a black cap. Dark-phase adults are dark brown, and intermediate phase birds are dark with somewhat paler underparts, head and neck. All phases have the white wing flash, which appears as a diagnostic double flash on the underwing. In breeding adults of all phases, the two central tail feathers are much longer than the others, spoon-shaped, and twisted from the horizontal.
+'''Pale Adult'''
+*Black cap
-Juveniles are even more problematic to identify, and are difficult to separate from Arctic Skua at a distance on plumage alone.
+*Dark upper parts
+*White underneath with brown breast band and flank bars
+*White flash on outer wing
+'''Dark Adult'''  all dusky-brown  body<br />
+'''Juveniles''' and '''immature''' variably mottled buff/brown
+====Similar Species====
+* [[Arctic Skua]]
 ==Distribution==
-This species breeds in the far north of Eurasia and North America. It is a migrant, wintering at sea in the tropical oceans.
+Far north of Eurasia and [[North America]]. It is a migrant, wintering at sea in the tropical oceans.
 ==Taxonomy==
-The Pomarine Skua, Stercorarius pomarinus, known as Pomarine Jaeger in North America, is a seabird in the skua family Stercorariidae. Its relationships are not fully resolved; its mitochondrial DNA is most similar to the Great Skua [Blechschmidt et al., 1993], but from morphology and behavior, it is closer to the lesser skuas (such as the Arctic Skua). The most likely explanation is extensive hybridization between the Great and one species of lesser Skuas, which resulted in a hybrid population that eventually evolved into a distinct species, the Pomarine Skua; or alternatively between the Pomarine and a species of Southern Hemisphere skua, with the Great Skua being the hybrid offspring, perhaps appearing as recently as the 15th century [Blechschmidt et al., 1993; Furness and Hamer, 2003]. Judging from characteristics of the skeleton and behavior, the former seems more likely, as the Pomarine Skua shares several similarities with the "Catharacta" Skuas, while the Great Skua does not seem much different from its Southern Hemisphere relatives.
+This is a [[Dictionary_M-O#M|monotypic]] species<sup>[[#References|[1]]]</sup>.
+[[Image:Spatelraubm we 7.jpg|thumb|350px|right|First year bird<br />Photo © by {{user|storensten|storensten}}<br />Oberkirch, [[Switzerland]], December 2010]]
-The mtDNA difference between the Pomarine and the Great Skua is one of the smallest between any two vertebrate species yet analyzed, being less than the variation found between different individuals of wide-spread species. The apparent capability for hybridization has led to the abolition of the separate genus Catharacta for the Southern Hemisphere and Great Skuas.
 ==Habitat==
-It nests on arctic tundra and islands,
+It nests on arctic tundra and islands
 ==Behaviour==
-It lays 2-3 olive-brown eggs in grass lined depressions. Like other skuas, it will fly at the head of a human or other intruder approaching its nest. Although it cannot inflict serious damage, the experience is frightening and painful.  It has many harsh chattering calls and others which sounds like which-yew.
+====Breeding====
+It lays 2-3 olive-brown eggs in grass lined depressions.
+====Diet====
+Its diet includes lemmings and other rodents on the breeding grounds.
-This bird feeds on lemmings and other rodents on the breeding grounds and also robs gulls, terns and even Gannets of their catches; it will also kill birds up to the size of Common Gull. Like most other skua species, it continues this piratical behaviour throughout the year, showing great agility as it harasses its victims.
+It will also kill birds up to the size of Common Gull.
+====Vocalisation====
+{{ Audio|Stercorarius pomarinus (song).mp3 }}
-==Bird Song==
+==References==
-<flashmp3>Stercorarius pomarinus (song).mp3</flashmp3><br />
+#{{Ref-Clements6thDec10}}#Wikipedia
-''[[Media:Stercorarius pomarinus (song).mp3|Listen in an external program]]''
+#Birdwatchers Pocket Guide ISBN 1-85732-804-3
+#Collins Pocket Guide to British Birds 1966
+#Collins Field Guid 5th Edition
+{{ref}}
 ==External Links==
-*[http://www.birdforum.net/pp_gallery/showgallery.php?si=+Stercorarius+pomarinus&x=16&y=8&perpage=12&sort=1&cat=all&ppuser=&friendemail=email%40yourfriend.com&password= View more images of Pomarine Jaeger in the gallery]
+{{GSearch|"Stercorarius pomarinus" {{!}} "Pomarine Skua" {{!}} "Pomarine Jaeger" }}
-*[http://www.aviceda.org/abid/birdimages.php?action=birdspecies&fid=41&bid=519 View more images of this species on the ABID]
+{{GS-checked}}1
-[[Category:Birds]]
+<br />
+<br />
+[[Category:Birds]] [[Category:Stercorarius]] [[Category:Bird Songs]]