Seal studies on Bird Island
There are three seal species that commonly come ashore (haul out) at Bird Island, to breed, moult, and rest: Antarctic fur seal (Arctocephalus gazella), southern elephant seal (Mirounga leonina) and leopard seal (Hydrurga leptonyx). The most abundant, and the main focus of studies at Bird Island, is the Antarctic fur seal, which is not a ‘true’ seal but an otarid (eared seal), a group that includes fur seals and sea lions. Antarctic fur seals are important predators of Antarctic krill and fish species dependent on the krill in the Scotia Sea ecosystem. Studies of fur seal ecology tell us about what is happening in the marine environment; because of its size, abundance and accessibility, the Antarctic fur seal is an excellent research species to investigate diet, physiology, behaviour, genetics, life history and population dynamics.
Antarctic fur seals breed between mid-November and early January and approximately 70,000 pups are born on Bird Island. Mothers rear their pups for up to four months and weaning occurs in April. Mothers combine short (2–14 days) feeding trips to sea with periods ashore (1–4 days) suckling their pups on energy-rich milk. During winter, many weaned pups and older juveniles stay around the island so that there is not a single month of the year without fur seals present. Antarctic fur seals were almost extinct by the early 20th Century, as they were hunted for their luxurious fur. Bird Island was one of the places where the recovery of the species started, after the discovery of a small breeding colony in 1930. Antarctic fur seal research on the island started in 1958 and continued during intermittent studies until 1981, when the British Antarctic Survey established their permanent year round base and continuous annual monitoring was possible.
Antarctic fur seal monitoring
Demography, life histories and population dynamics; female seasonal performance and attendance (to their pups); and diet
Leopard seal studies
Total seasonal counts, seasonal number of individuals, opportunistic diet data collection