NSW launches H5N1 vaccine trial for endangered birds as avian flu spreads

Taronga Zoo began vaccinating birds against H5N1 avian influenza this week, marking the start of what NSW officials hope will become a statewide effort to protect endangered species from a virus that has already infected at least 16 birds across the state. The initial trial involves 70 animals spanning 18 species—little penguins, black cockatoos, emus, owls, and various raptors and waterfowl—all housed at the zoo where they can be monitored closely for 14 days after receiving their second dose.

The decision to vaccinate reflects the growing threat posed by H5N1 in New South Wales. Agriculture Minister Tara Moriarty confirmed that 16 cases have been detected so far, including one in the Illawarra region confirmed on Thursday night. Unlike South Australia, where the virus has jumped to mammals including seals and a red fox, NSW has so far seen infection only in birds. The vaccine itself is not licensed for poultry or mammals—only for rare and endangered species—leaving commercial chicken farms and household pets outside the scope of this initial rollout.

Environment Minister Penny Sharpe acknowledged the uncertainty at the heart of the program. "We don't know how the vaccine will work in our birds," she said, explaining why the trial beginning this week is essential. The work will measure both the safety and effectiveness of the vaccine across a broader range of species than have been tested before, and will help determine how often different species need to be revaccinated. Dr. Karrie Rose, a veterinary pathologist at Taronga Zoo, emphasized that the organization is not waiting for trial results to begin operational vaccinations of its own animals while simultaneously supporting the National Parks and Wildlife Service in vaccinating wild populations.

The expansion to wild birds presents a logistical puzzle that has shaped where the program will focus first. Little penguins in Manly and on Barunguba Montague Island off Narooma have been selected as priority populations, not by chance but by biology. Ingrid Emery, executive director of conservation programs at the NSW Department of Climate Change, Energy, the Environment and Water, explained that little penguins are "very faithful to where they nest"—they return to the same locations reliably, which makes it possible to catch them between water and nest box, vaccinate them, and then recapture them 28 days later for a second dose. For most wild birds, this kind of recapture would be nearly impossible. The logistical complexity of accessing remote locations and finding the same individual bird weeks later is precisely why this population was chosen to pilot the approach.

While the vaccine trial proceeds, NSW authorities are urging backyard bird owners to implement immediate biosecurity measures. Agriculture Minister Moriarty advised keeping chicken feed and water in shelter, away from potential contamination by wild birds, and cautioned against using dam water for backyard flocks. The state has received more than 5,000 calls to its Emergency Animal Disease Hotline since it opened in June at the State Coordination Centre in Orange, suggesting widespread concern among residents.

The vaccine rollout raises questions about what comes next for commercial poultry and household pets. Dr. Joanne Coombe, NSW's chief veterinary officer, noted that ongoing conversations are taking place about vaccinating poultry, though a different vaccine may be required. For now, the focus remains on the trial at Taronga Zoo and the carefully planned expansion to wild populations, with little penguins serving as the test case for whether vaccination can work as a conservation tool in the face of a spreading virus.