Australia on Sunday confirmed its first case of H5N1 bird flu in a mammal, with the deadly ​virus found in a long-nosed fur seal in South ‌Australia state.

Australia has been grappling with rising cases of the highly pathogenic avian influenza after it landed in the country in June.

South Australian authorities ​confirmed the nation’s first mammalian detection in the seal, ​found at the coastal town of Beachport, about 310 ⁠km (192 miles) south of Adelaide, the state capital.

The seal, one ​of an estimated population of 100,000 in the state’s waters, was found ​dead with no signs of injury, the authorities said.

Its death “does not appear to be associated with other sick or dead marine mammals,” Federal Agriculture ​Minister Julie Collins said in televised remarks.

“Once the H5 ​bird flu is spreading in the natural environment it is not possible to avoid significant ‌losses,” ⁠Collins added.

Australia reported its first mass seabird deaths from the virus this month, marking an escalation of the outbreak that began after the virus was first detected in migratory seabirds before ​spreading to native ​species.

The virus ⁠has yet to show up in Australia’s poultry or agriculture, according to the federal government, which ​said on Friday that 297 cases have ​so far ⁠been confirmed nationwide.

Australia was the last continent to report bird flu, although the virus was detected in late 2025 on the ⁠sub-Antarctic ​territory of Heard Island. More than ​13,000 baby seals were killed by the virus on the island, according to ​local media.