A severe outbreak of bird flu is wreaking havoc on remote islands near Antarctica, leading to the death of approximately 13,000 seal pups, as well as penguins and seabirds, according to researchers.
Drone surveys conducted by the Australian Antarctic Program in both October and January revealed haunting images of seal pup carcasses strewn across the gray volcanic beaches of Heard and McDonald Islands, with insights shared by senior researcher Jarrod Hodgson.
These islands, situated around 2,485 miles (4,000 kilometers) from mainland Australia, have historically been a haven for various breeding birds and marine mammals.
Mortality rates among southern elephant seal pups were estimated to be as high as 76%, affecting a population of around 17,000. In certain locales, the death rate soared to 97%.
Hodgson remarked, “We currently lack information on how breeding adult southern elephant seals were affected by this outbreak.”
Furthermore, data collected in January indicated that several hundred adult king penguins on Heard Island had also perished, with researchers noting that these deaths were exceeding normal mortality rates.
Julie McInnes, a wildlife biologist, stated, “This detection of H5 bird flu at Heard and McDonald Islands marks the virus’s first appearance in an Australian external territory and highlights its continuing spread across the sub-Antarctic.”
McInnes, who is the lead author of the study, added, “Our findings reflect patterns seen on other sub-Antarctic islands, such as South Georgia, where elephant seals have been significantly affected.”
As of February, neither mainland Australia nor New Zealand reported cases of the H5N1 strain, which has circulated among birds globally and impacted certain mammals.
Genetic analysis suggests that the H5 bird flu likely reached these islands via wildlife from the Crozet Islands, roughly 1,800 km away, probably arriving around August 2025.
The research has been published in the scientific journal BioRxiv, although it is still pending peer review.
