Australian authorities announced Friday that the country has found its first suspected case of H5N1 bird flu on the mainland, discovered in a remote corner of the nation’s southwest.
A brown skua — a type of migratory seabird — was discovered in Western Australia’s Cape Le Grand National Park and tested positive for avian influenza. Additional testing is underway to identify the exact strain, according to state Agriculture Minister Jackie Jarvis.
“We are taking the suspected case of H5 bird flu seriously,” Jarvis said. “If this is confirmed H5 bird incursion, there will be a rapid and coordinated national response.”
The highly aggressive H5 strain of bird flu has been spreading through wild bird and mammal populations since 2021, resulting in the deaths of millions of animals. It has also made its way into poultry and dairy farm operations and has infected some agricultural workers.
Until now, Australia stood alone as the only continent without a confirmed mainland case of the deadly strain. H5 was previously confirmed on Heard Island, an Australian sub-Antarctic territory, in late 2025.
In anticipation of the virus potentially reaching its shores, Australia has spent recent years strengthening biosecurity measures at farms, monitoring shorebirds for signs of disease, vaccinating at-risk species, and running response simulations.
“While, if confirmed, this would obviously be a very concerning development, Australia has spent the past few years preparing for this likelihood,” Environment Minister Murray Watt said in a statement.
Jarvis said results confirming whether the deceased brown skua was infected with H5 bird flu are expected by Saturday. She also noted that a second sick bird — a giant petrel — was found in the same location and is also being tested for influenza.
Wayne Boardman, a wildlife veterinarian and associate professor at Adelaide University, expressed deep concern about the potential impact on Australia’s native animals.
“This strain of bird flu has caused huge die-offs of birds and sea mammals,” he said.
“My concerns are that if the H5N1 avian flu virus is confirmed, it will pose a huge risk to some of our more endangered shorebirds, some of our coastal raptors, and our precious, unique, endemic and endangered Australian sea lions, whose population is precarious,” Boardman added.
