Only a few weeks ago, H5N1 avian influenza appeared to be a distant concern for New Zealand. While isolated cases had been detected in Australia, the advice remained much the same: be alert, but avoid unnecessary alarm.
Recent events suggest that assessment now deserves updating.
South Australia has reported three mass mortality events involving more than 1,000 crested terns across remote offshore islands. Authorities believe the deaths are most likely the result of H5N1 avian influenza. At the same time, Tasmania is investigating further deaths among little penguins and other seabirds as surveillance expands across Bass Strait.
Importantly, Australian authorities are not responding with panic. Instead, they have significantly increased surveillance using ground teams, aircraft, helicopters and drones. Dead birds are being collected and tested, affected areas are being monitored, and wildlife experts continue to assess how the disease is spreading through wild bird populations.
That measured response deserves attention.
The situation has clearly changed, but not every aspect of the risk has changed equally.
There remains no evidence of widespread infection in Australian poultry or livestock, and authorities have not reported mass mortality events among wild mammals. Those are reassuring developments. The principal concern continues to be wild seabirds, particularly colonial nesting species where close contact allows the virus to spread rapidly.
For New Zealand, geography provides no guarantee of protection. Migratory seabirds regularly cross the Tasman Sea, and Australia is now much closer to home than outbreaks occurring in Europe or North America ever were. Whether H5N1 reaches New Zealand’s wild bird populations cannot be predicted, but the possibility has undoubtedly become more relevant.
That does not mean outdoor recreation should change dramatically.
There is no reason for people to stop enjoying beaches, estuaries or coastal reserves. However, anyone encountering unusual numbers of sick or dead birds should avoid handling them directly and report the observations through the appropriate biosecurity channels. Early reporting remains one of the most valuable tools available for detecting any new incursion.
The outbreak also reminds us that biosecurity is not simply about protecting agriculture. Healthy seabird populations are an important part of New Zealand’s coastal ecosystems. They contribute to nutrient cycling, indicate the health of marine environments, and are part of the natural heritage enjoyed by birdwatchers, anglers, trampers and everyone who spends time outdoors.
When CORANZ first examined H5N1, the message was one of concern without overreaction. That principle still holds true.
The difference today is that Australia is now experiencing significant wildlife mortality rather than isolated cases. Good biosecurity requires us to recognise when circumstances change and respond accordingly. Not with panic, but with increased vigilance, careful monitoring and decisions guided by evidence rather than speculation.
The best biosecurity outcomes are often the ones that go unnoticed because they prevent problems before they become crises. As Australia responds to this evolving situation, New Zealand should continue to prepare carefully, strengthen surveillance where appropriate, and remain ready to act should the evidence show that the risk has moved closer to our own shores.
Not much can be done to stop or fix it.