Brown Skua (Stercorarius antarcticus) [XC162224]
by Andrew Spencer from Port-aux-Fran\u00e7ais, France (call)
Brown Skua (Stercorarius antarcticus) [XC623838]
by Kevin Guille from Port-aux-Fran\u00e7ais, France (call)
Subspecies
Great Skua (Catharacta skua), Southern Skua (Catharacta lonnbergi), Southern Skua (Catharacta antarctica) and South Polar Skua (Catharacta maccormicki) (Sibley and Monroe 1990, 1993), cross-regional species, are retained as separate species contra Christidis and Boles (1994) and Turbott (1990) who include lonnbergi and antarctica as subspecies of Great Skua (Catharacta skua) and AERC TAC (2003) who include South Polar Skua (Catharacta maccormicki) as a subspecies of Great Skua (Catharacta skua).
Occasional hybridization reported with South Polar Skua (Catharacta maccormicki) and with Chilean Skua (Catharacta chilensis), but hybrids very rare. Subspecies hamiltoni differs only slightly from nominate antarctica. Subspecies lonnbergi has been considered a separate species. Proposed subspecies clarkei and intercedens invalid, and nowadays included in lonnbergi. Name lonnbergi sometimes erroneously spelt loennbergi, but removal of Scandinavian umlaut does not justify addition of "e".
The following 3 subspecies are recognised:
antarctica (Lesson, 1831) - Falkland Is. and south-eastern Argentina. Winters off south-eastern South America.
hamiltoni (Hagen, 1952) - Tristan da Cunha and Gough I. Winters near breeding areas.
lonnbergi (Mathews, 1912) - Antarctic Peninsula, subantarctic islands of Atlantic, Indian and Pacific Oceans. Winters near or slightly dispersed from breeding areas. Considered by some authors to be a distinct species, Southern Skua (Catharacta lonnbergi).
Notes
Previously four subspecies of Catharacta skua, were nominate skua, lonnbergi, antarctica and hamiltoni. They have now been split into four distinct species, Great Skua Catharacta skua, breeds in northern hemisphere, Southern Skua Catharacta antarctica, breeds Falkland Islands and Patagonia, Brown Skua Catharacta lonnbergi, circumpolar, breeding on subantarctic islands and the Antarctic Peninsula, and Chatham Island, and Chilean Skua Catharacta chilensis.