The taxonomy, identification, and distribution of skuas (currently genus Stercorarius but formerly Catharacta, AOU 2000) have long been, and continue to be, the subject of debate and uncertainty. Most authors now recognize six taxa constituting four species: the Great Skua (Stercorarius skua), breeding in the North Atlantic; the Chilean Skua (S. chilensis), breeding around southern South America; the South Polar Skua (S. maccormicki), breeding around Antarctica; and the Brown Skua (S. antarctica, with subspecies antarctica, lonnbergi, and hamiltoni), breeding widely on islands in the southern oceans (Malling Olsen and Larsson 1997).