South Polar Skua
Category: Sea Bird Other
The South Polar Skua is a southern gull-like bird.
The scientific name for this species is Stercorarius maccormicki. The species was named by Saunders in 1893.
The South Polar Skua has been called the MacCormick’s skua, for the first person to collect a specimen of the species. The South Polar Skua and Great Skua are occasionally placed in a separate genus, Catharacta.
The name skua- probably derives from its call, which sounds like the name. Because these birds will eat the young and dead of other sea birds, the South Polar Skua are sometimes called the raptor of the south.
The South Polar Skua is around 21 inches in length fully grown. The South Polar Skua is larger than the Pomarine Skua and Arctic Skua, and has a barrel chest the others lack.
In its dark phase, most adults have a dark brown body, nearly black wing feathers large white patch on its primaries. There is a paler morph and brown morph. All of them have a broad, short tail. Juveniles are more uniformly brown but may be distinguished by their blue bill base. The South Polar Skua has the most grey coloring of all the skuas, whereas other species have more warm brown coloring.
The South Polar Skua have dark eyes and a dark grey bill at maturity. The males and females have a similar appearance, though the male is slightly smaller than the female. Both have a similar appearance to the North Atlantic Skua that is related to it. The species has a smaller head and narrower wings than related species.
The South Polar Skua have a strong direct flight powered by shallow wing beats.
While all South Polar Skuas were once thought to be a single species, they are now shown to nest near each other without interbreeding. There may be as many as five species.
The South Polar Skua feed on krill, squid, and fish. The South Polar Skua will raid Adelie penguin colonies for eggs, chicks, and carrion. The South Polar Skua will rob gulls and terns of their catches. The South Polar Skua will eat rabbits and other mammals if available.
Part of the South Polar Skua’s range overlaps with the brown skua. In those areas, the South Polar Skua primarily eats fish because the Brown Skuas control the penguin colonies as a source of food.
The South Polar Skua only come ashore to breed. The South Polar Skua typically lay two olive brown eggs in November and December, the Antarctic summer. The South Polar Skua nest primarily in Antarctica. The South Polar Skua prefer sheltered areas next to penguin colonies.
The male helps feed the female, who does most of the incubating and rearing of the young. The incubation period is around four weeks. The young have their first flight at seven to eight weeks of age. They first breed at five to six years of age.
While the South Polar Skua ranges throughout the world in the summer, it is a sea bird, rarely coming ashore. The South Polar Skua nests on barren ground in the Antarctic south.
The South Polar Skua winters in Australia, South America, and sometimes comes up to North America. The South Polar Skua have been seen at the South Pole and are known as the world’s most southerly bird.
The South Polar Skua is classified as being of least concern by the IUCN.
A group of skuas is called a shishkab.