South polar skua

South Polar Skua Catharacta maccormicki Photo: Frederique Olivier

Two species of skuas breed on islands in the Southern Ocean: the south polar skua (Catharacta maccormicki) which breeds on the Antarctic Continent, and the subantarctic skua (Catharacta lonnbergi), which breeds further north on subantarctic islands. The south polar skua is the smaller of the two species.

South polar skuas arrive at their breeding colonies in late October to mid-December. The eggs hatch in late December to late January after an incubation period of 24-34 days.

During the summer months, south polar skuas prey on eggs and young of Adélie Penguins near the coast, while other skuas feed solely on fish and krill. South polar skuas are often seen following ships at sea. Both species migrate northward after the breeding season.

Both species are winter visitors to Australia, and the South polar skua has been recorded as far north as Greenland and the Aleutian Islands.

Many skuas nest in close association with their prey. Their nests are a shallow depression on the ground and are generally found in sheltered locations on rocky outcrops, moss covered cliffsides or valley floors.

Southern giant-petrel and other skuas are infrequent predators on unattended nests and wandering chicks. Some eggs and chicks are lost each season to exposure.

Links

Taxonomic information on the south polar skua

Australian Antarctic Science (AAS) projects relating to skuas

Australian Antarctic Magazine - Heard Island's seabirds under scrutiny

Monitoring for long-term or cumulative impacts in Southern Ocean seabirds

See more information on the Australian Antarctic scientific research program