The gentoo penguin has become the first bird on an Australian territory to test positive for the deadly H5N1 bird flu. Scientists confirmed the virus on Heard Island, a sub-Antarctic Australian territory located 4,000 km from Perth and 1,700 km north of Antarctica. The virus was first found in southern elephant seals there in November 2025. Now, fur seals and gentoo penguins also carry the virus. Professor Hugh Possingham, vice-president of BirdLife Australia, called this "a very concerning development." He said, "The gentoo penguins of Heard Island are now the first birds in an Australian territory to test positive for this virus that has devastated wildlife around the world. They will certainly not be the last." Possingham warned that H5N1 could threaten other unique Australian birds, like the Heard Island cormorant and sheathbill. The federal government said Australia remains free of H5N1 overall and the new cases do not greatly raise the risk. Agriculture Minister Julie Collins stated the government is serious about bird flu and has invested over $100 million to prepare and respond. "While continued detections of H5 bird flu on Heard Island are not unexpected, this reinforces the need to prepare for a potential outbreak," she said. The H5N1 virus arrived in the Antarctic region during the 2023-24 season and has spread across various sub-Antarctic islands. Dr Michelle Wille from the University of Melbourne described the virus as "catastrophic for wildlife" and warned it could spread to Australian and New Zealand islands like Macquarie Island, then to mainland Australia. She stressed that surveillance and preparation are crucial to handle this threat as it may come from the southern or northern routes.