Hundreds of elephant seals have been found dead, apparent victims of the deadly H5N1 avian flu virus. The event is raising concerns among scientists that the virus could spread to the continent's penguin colonies leading to a catastrophic mass die-off. The virus was first found in skua birds in October 2023 on Bird Island, part of UK's territory of South Georgia and South Sandwich Islands. Antarctic wild life have no natural immunity to the highly contagious, novel virus probably transmitted by migratory birds from South America where it has killed millions of sea birds and mammals. Some seabirds in the UK, where the outbreak was first reported, have shown signs of developing immunity.
So far, eight sites in the Antarctic have confirmed seabird flu deaths. Twenty more sites are pending confirmation. Penguins are particularly susceptible as the gather in close proximity for the breeding season.
[photo] Previous outbreaks in Argentina, South Africa and Chile show how susceptible they are to the disease. If mass mortality events among penguins occur, one scientific paper said, "it could be the largest ecological disaster of modern times". No confirmed cases have been detected on the mainland of the southernmost continent, but is expected to arrive in the coming months. Portions of South Georgia are now closed to tourists as part of precautions to deter the spread of the disease.
Seabird colonies around the world have suffered losses of 50-60% due to the highly pathogenic virus. Twenty thousand sea lion are estimated to have died in Chile and Peru.
[king penguin colony 1982 on Pig Island; photo credit: H. Weimerskirch]
