Bird flu is spreading in Antarctica, with hundreds of elephant seals being found dead. There are fears this could cause “one of the greatest ecological disasters of modern times” if the highly contagious virus reaches remote penguin populations.
The virus was first reported among the brown skua on Bird Island, off the coast of South Georgia. Since then, researchers and observers have reported mass deaths of elephant seals, as well as increased mortality of fur seals, kelp gulls and brown skua at several other locations. Cases have been confirmed 1,500 kilometers west of South Georgia, among the southern fulmar in the Falkland Islands.
Dr. Meagan Dewar, President of Antarctica Wild animals Health Network, told the Guardian that the situation among southern elephant seals was worrying. “We’ve had mass deaths in some locations, numbering in the hundreds,” she said. “There’s a good chance it’s bird flu.”
So far, tests have confirmed bird flu deaths at eight locations in Antarctica, and the disease is suspected with confirmation from tests still pending at 20 other locations where animal deaths have occurred.
Researchers reported that a number of elephant seals showed symptoms of bird flu, such as difficulty breathing, coughing and build-up of mucus around the nose. Lethargy, spasms and the inability to fly are symptoms in birds.
While a number of seabird cases have been confirmed, many cases – including elephant seals – are still considered suspicious, pending laboratory results.
So far, no cases have been recorded on the Antarctic mainland – home to unique ecosystems that are among the most isolated in the world – but the disease is expected to emerge in the coming months as the birds move around.
Dewar said: “It’s devastating to see that happen and take in all the cases we’re getting.”
Penguins begin to gather as breeding season begins, and this close contact makes them especially vulnerable. Previous outbreaks in South Africa, Chile and Argentina show susceptibility to the disease.
“If the virus begins to cause mass mortality in penguin colonies, it could be one of the greatest ecological disasters of modern times,” researchers wrote in a pre-print. research paper last month.
Many Antarctic species are found nowhere else, so the regional impact of the spread of highly pathogenic avian influenza (HPAI) is unknown.
The Scientific Committee on Antarctic Research recently said: “Given the dense breeding colonies of wildlife in the Antarctic and sub-Antarctic regions, HPAI is expected to have devastating impacts on wildlife and lead to catastrophic breeding failures and mortality in the region. ”
The virus has a an estimated 20,000 sea lions in Chile and Peru. Dewar said: “If we have outbreaks similar to what we have seen in South America, it could have very significant consequences. Emperor penguins and chinstrap penguins have declined significantly, so if we have large outbreaks of these species it could put further pressure on those colonies.”
The current outbreak of the highly contagious H5N1 variant – which started in 2021 – is estimated to have killed millions of wild birds. The tension spreads Antarctica is clade 220.127.116.11b, which has decimated bird populations in Britain, continental Europe, South Africa and the Americas, with seabird colonies suffering losses of 50% to 60%. The H5N1 strain has not yet reached Oceania
Dr. Michelle Wille, from the University of Sydney, who is helping to record deaths, said: “It is terrible news that it is now in the sub-Antarctic region, and we are very concerned about the spread of viruses into Antarctica. In addition to the negative impacts on animals, the ‘removal’ of large numbers of animals from the Antarctic ecosystem could also have long-term ecosystem effects.”
Researchers from the British Antarctic Survey and the UK government’s Animal and Plant Health Agency identify possible cases, test them and share data. It’s challenging to record what’s happening because of Antarctica’s size and the small number of people monitoring it. A number of reports of mass deaths have been received via tour ships.
Many places in South Georgia are now closed tourists and even researchers must go through a number of procedures to get there in an effort to stop the spread of the disease, said Dr. Michael Wenger, who trained as a marine biologist and has worked as a guide in Antarctica for 18 years.
He added: “It is difficult to estimate numbers in normal situations because the area is huge and there are many animals. Now that the areas are closed, it is even more difficult.”