Australia has recorded its first confirmed case of H5N1 bird flu in a local mammal after the virus was detected in a long-nosed fur seal in South Australia.
The seal was found dead near Beachport, about 310 kilometres south of Adelaide, with authorities saying there were no visible signs of injury. The discovery marks a further development in Australia’s bird flu outbreak, which has intensified since the virus arrived in the country in June.
South Australian authorities said the seal was among an estimated population of around 100,000 fur seals living in the state’s waters. Federal Agriculture Minister Julie Collins said the animal’s death did not appear to be linked to other sick or dead marine mammals.
Authorities have warned that preventing significant losses could become difficult once H5N1 establishes itself in the natural environment. South Australia’s chief veterinary officer, Skye Fruean, said seals face a heightened risk because they live close to wild birds along coastal rocky areas where they could be exposed to high levels of the virus.
Australia was the last continent to report bird flu, although H5N1 had previously been detected on the sub-Antarctic Heard Island in late 2025. Local media reported that more than 13,000 seal pups died from the virus on the island.
The latest discovery comes after Australia recorded its first mass seabird deaths linked to H5N1 earlier this month. The outbreak initially emerged after the virus was detected in migratory seabirds before spreading to native wildlife.
Despite the spread among birds and now mammals, the Australian Government said H5N1 has not been detected in the country’s poultry or agricultural sector. As of Friday, 297 cases had been confirmed nationwide.
The detection in a mammal is being closely watched by authorities as Australia continues efforts to contain the highly pathogenic virus and limit its impact on wildlife.
