MacCormick’s skua
The south polar skua (Stercorarius maccormicki ) is a large seabird in the skua family, Stercorariidae. An older name for the bird is MacCormick's skua, after explorer and naval surgeon Robert McCormick, who first collected the type specimen. This species and the other large skuas, such as the great skua, are sometimes placed in a separate genus Catharacta.
South polar skuas are large predatory seabirds. Adults are greyish brown above and have a whitish or straw-brown head and underparts. They have longish bills with a hooked tip, and webbed feet with sharp claws. They look like large dark gulls but have a fleshy cere above the upper mandible. The skuas are strong, acrobatic fliers. They are generally aggressive in disposition. Potential predators approaching their nests will be quickly attacked by the parent birds, which usually target the heads of intruders - a practice known as 'divebombing'.
South polar skuas breed on snow-free areas of Antarctic coasts and winter at sea in the Pacific, Indian, and Atlantic Oceans.
South polar skuas are social birds and during feeding, they gather in large and very noisy flocks that may contain up to 100 individuals. They hunt by day diving for fish, plucking their prey on the surface, or stealing food from other seabirds. They won't even hesitate to grab a gull or other bird with their bill and shake it violently to force it to disgorge its catch. South polar skuas are very powerful, fast fliers and are generally silent away from their breeding grounds.
South polar skuas are carnivores (piscivores) and scavengers. They eat mainly fish, but also other birds, eggs and young of penguins, rabbits, and carrion.
South polar skuas are monogamous and stay with their mate for life. They usually breed in loose colonies but some pairs may nest solitarily. Their breeding season occurs from November and until February. The female lays 2 eggs is an unlined scrape on the ground and both parents incubate them within a month. The chicks are precocial and leave nest soon after hatching. Usually, only one chick survives to fledge which occurs at the age of 45-50 days. Young skuas generally reach reproductive maturity and begin to breed when they 5 to 6 years old.
There are no major threats to South polar skuas at present. However, these birds have low reproductive success and chick survival; they also suffer from severe weather and pollution of their habitat.
According to the IUCN Red List, the total population size of the South polar skua is around 10,000-19,999 individuals, equating to 6,000-15,000 mature individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and their numbers today are stable.