Gentoo penguins the first birds on Australian territory to contract H5N1 as bird flu spreads | Bird flu
A Gentoo penguin became the first bird to test positive for H5N1 bird flu on Australian soil, with samples taken confirming the virus had spread to an island below Antarctica.
The deadly and contagious strain of bird flu, which has already killed millions of seabirds, wild birds and fowl abroad, was confirmed in southern elephant seals on Heard Island in November 2025.
Fur seals and gentoo penguins have now tested positive for the virus after more samples were collected by Australian Antarctic Program scientists on a second trip to Heard Island, according to the federal government.
The island is an Australian territory located approximately 4,000 km southwest of Perth and 1,700 km north of Antarctica.
Prof Hugh Possingham, deputy chief executive of BirdLife Australia, said the spread of the virus to other species was “an extremely worrying development”.
“Gentoo penguins on Heard Island are now the first birds on Australian soil to test positive for this virus that is devastating wildlife worldwide,” Possingham said. “They definitely won’t be the last.”
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He said H5N1 could pose a significant threat to the survival of other Australian birds, including the Heard Island cormorant and Heard Island warbler, species found nowhere else on Earth.
“Since the virus was first suspected on Heard Island and subsequently confirmed, we have been asking the government directly how wildlife protections have been stepped up to protect Australian wildlife from this virus that is so clearly on the move,” he said.
“We are disappointed that these questions remain largely unanswered.”
In an update on Tuesday, the federal government said Australia was free of H5N1 and additional detections did not significantly increase the risk.
Agriculture minister Julie Collins said the government was taking the threat of bird flu seriously and was investing more than $100 million to strengthen preparedness and response capacity.
“While the ongoing detections of H5 bird flu on Heard Island are not unexpected, this reinforces the need for Australia to continue focusing on preparing for a potential outbreak,” he said.
“Biosecurity is a shared responsibility and Australia’s success depends on close collaboration between governments, industry, communities and individuals.”
The H5N1 virus entered Antarctica during the 2023-24 season, with the first detections in South Georgia and then on the Antarctic peninsula. The following year it spread to Marion Island and the French sub-Antarctic islands of Kerguelen and Crozet, located about 500 km from Heard and McDonald islands.
Dr Michelle Wille, an expert on bird flu viruses from the University of Melbourne, described the disease as “catastrophic for wildlife” and said H5N1 had already spread thousands of kilometers across the ocean.
He said it was plausible that the virus could theoretically spread to Australia from where it is now. [and] New Zealand’s sub-Antarctic islands, such as Macquarie Island. And from there it’s not too far to get to Australia.
“We face the risk of this virus reaching Australia via a potential southern route or northern route,” he said, making surveillance and preparedness extremely important.
