H5 bird flu and Australia’s wildlife: the risks to our native species and how to help

This page explains the risks H5 bird flu poses to Australia’s native wildlife, what to do if you see affected birds or wildlife, and what can be done to help. For guidance on protecting cats, dogs and backyard birds, see our companion page, H5 bird flu and your pets.

Why is wildlife at risk from H5 bird flu?

H5 bird flu is a disease of wild birds and the animals that live alongside them. The strain now circulating — H5N1 clade 2.3.4.4b — has spread across the world since 2021 with an impact never seen before, killing wild birds in their millions and crossing into many species of wild mammals. Where a virus like this reaches animals that live and breed in large, dense groups, it can spread very quickly. There is no treatment for H5 bird flu in wildlife.

That is the heart of the concern for Australia. Our coasts and islands hold internationally significant breeding colonies of seabirds, and our beaches and offshore islands are home to seals and sea lions found nowhere else. Many of these animals have never encountered this virus, so how badly they will be affected is impossible to predict.

How you can help

Community reports are how surveillance teams track where the virus is and identify locations that need investigation. Australians have made more than 25,000 reports to the Emergency Animal Disease Hotline since the outbreak began, and the first confirmed mammal case in the country came from a member of the public reporting a dead seal on a beach. Even a single sick or dead bird is worth reporting, and dead birds can stay infectious for up to 30 days at 20°C, and longer in colder conditions - so carcasses matter as much as visibly sick birds and wildlife.

Should I call WIRES?

The wildlife rehabilitation sector is not expected to play an active operational role during outbreaks. WIRES’s role at this stage is to continue risk-mitigation planning, support community awareness, and comply with government directives on the reporting, rescue and care of affected animals. WIRES advise that if you have found an injured or orphaned native animal and are unsure about what to do, you can call 1300 094 737 for advice, otherwise, for sick and dead birds and wildlife, call the 24-hour hotline on 1800 675 888.

 

Download these Department of Agriculture, Fisheries and Forestry resources to help educate and raise awareness of H5 bird flu. Infographics relating to pets are on our H5 bird flu and pets page.

 

Which birds are most affected

Overseas, the wild birds hit hardest have been those that congregate in numbers: seabirds such as terns, gulls, gannets and albatrosses; waterfowl such as ducks, swans and geese; shorebirds; and the predatory and scavenging birds — eagles and others — that feed on infected animals. Terns, gulls, gannets and albatrosses can transmit the virus rapidly once it reaches a colony.

Australia’s first confirmed mass death was at Baudin Rocks off Cape Jaffa on the South Australian coast in August 2026, where 49 greater crested terns were found dead and 35 more sick. Greater crested terns have borne the brunt since: South Australia has reported three further mass mortality events on remote offshore islands involving more than 1,000 of them, presumed to be H5 bird flu. Tasmania has recorded more than two dozen dead penguins within a week of the virus reaching the state, and a little penguin has been confirmed on Kangaroo Island.

The virus is also moving along the New South Wales coast. Detections at Narooma and Merimbula on the far south coast, in greater crested terns and a giant petrel, follow earlier cases at Eden, Hawks Nest and Wentworth — the last of these well inland on the Murray. Gulls travel long distances and move between the coast and inland waterways, and can carry the virus far beyond the beaches where it first appears. According to Burnet Institute chief health officer Suman Majumdar, Australians should expect further spread along coastlines, with mass mortality events in seabirds and marine mammals in the weeks ahead.

In August 2026 the Australian Government published a risk analysis ranking more than 2,000 native birds and mammals. It found 386 species at high to extreme risk. Five birds are rated at extreme risk: the Christmas Island frigatebird, Houtman albatross, Herald petrel, and the imperial shags of Heard Island and Macquarie Island. These are species that gather at only a few sites, where a single outbreak could affect a large share of the population.

How H5 bird flu affects seals and sea lions

Marine mammals that live in close contact with seabirds have been among the hardest hit wherever this virus has spread. In June 2026 H5 bird flu was confirmed on Heard Island — a remote sub-Antarctic Australian external territory roughly 4,000 kilometres south-west of Perth — where it was linked to the deaths of over 13,000 elephant seal pups, around three-quarters of the pups on the island. In April 2026 the southern elephant seal was listed as vulnerable on the IUCN Red List, in part because of bird flu mortality, and recovery is expected to take decades.

The Australian sea lion, Australian and long-nosed fur seals and southern elephant seal are the marine mammals identified as most at risk here, and dolphins are also in the high-risk categories.

Why the Australian sea lion is the pressing concern

Fewer than 10,000 Australian sea lions remain, with about 85 per cent of them in South Australia. One of the largest and most stable breeding colonies is on The Pages, small islands between Kangaroo Island and the mainland. In August 2026 South Australia reported three mass bird mortality events on remote offshore islands, involving more than 1,000 greater crested terns and presumed to be H5 bird flu; two were at The Pages. Infected terns have also been confirmed at Seal Bay on Kangaroo Island, another major sea lion site.

The species was already under pressure. Associate Professor Rachael Gray, a University of Sydney veterinarian who studies Australian sea lions, reports that government observers counted 84 dead pups across two visits to The Pages in the 2025 breeding season — a mortality rate above 34 per cent, against a recent average of 5 per cent. The deaths were largely attributed to the algal bloom, with a lack of food stressing mothers and pups.

Work is under way to build resilience. State and federal governments committed $1.4 million to worming pups and building shelters at colony sites, which Dr Gray describes as giving pups a better chance of growing well, so that when a threat like avian influenza arrives they are better placed to cope with it. She also notes one possible advantage: unlike other pinnipeds, Australian sea lion pups are born over an extended period rather than in a tight window, so a virus arriving when few pups are present might do less damage — though she says it is too early to tell.

Jack Gough, chief executive of the Invasive Species Council, has warned that mammal-to-mammal transmission moved quickly among seals when the virus reached South America and Antarctica, where around 30,000 elephant seals died, and that colony collapses are a realistic prospect here. For the Australian sea lion, he says, this could be an extinction-level event.

There is no ready answer for mammals. South Australian Environment Minister Emily Bourke has said there is no off-the-shelf vaccine for marine mammals, and that no country has found one in the five years this strain has been circulating. South Australia has told the federal government it is willing to explore the approach trialled in Hawaiian monk seals, while noting it is not an approved vaccination.

Native mammals and marsupials

Overseas, H5 bird flu has affected birds and mammals but has not been found to infect animals such as reptiles, fish and amphibians. Among mammals, the animals most often infected are those that prey on or scavenge birds, along with the marine mammals covered above. Several of our most distinctive mammals are scavengers.

The Australian Government’s risk assessment rates the Tasmanian devil and eastern quoll as the highest-risk land mammals. Wildlife Health Australia’s national coordinator, Dr Tiggy Grillo, has said the species that could be at risk in Australia include Tasmanian devils, quolls and the rakali, a native water rat - all scavengers that could encounter the virus through an infected carcass.

Almost nothing is known about how marsupials respond to this virus - because most marsupials live only in Australia. The one exception is the North American Virginia opossum, the only marsupial known to have been killed by H5 bird flu so far. Experts still describe the risk to Australia’s marsupials as a genuine unknown.

Preparation is already under way to protect a number of particularly vulnerable species. Perth Zoo, the only place in the world that breeds the endangered numbat, has roofed its previously open-air enclosures to stop wild-bird droppings falling onto the insects the numbats eat, and is looking at back-up diets to reduce that exposure further. Similar biosecurity work and “insurance populations” — secure captive groups held as a safeguard — are being established for quolls and other susceptible marsupials, so that a species could survive even if the virus reaches wild populations.

What happens next for Australia’s wildlife?

Authorities have been clear that this is the beginning of what is likely to be a long and difficult period for Australia’s wildlife. Once the virus is established in wild birds, it cannot be eradicated. Environment Minister Murray Watt has said he expects more mass mortality events in Australia, and that seeing them will be distressing for people. His stated aim is to keep affected species at population levels where they survive long term, while acknowledging the impacts will be serious.

Each year, large numbers of migratory birds arrive in Australia from the northern hemisphere, gathering in the same coastal wetlands and staging grounds as resident species. Where infected and uninfected birds mix in these dense congregations, the chance of transmission and further mortality events increases. There are serious concerns for the Coorong in South Australia — an internationally significant wetland where large numbers of water birds gather, and already touched by the virus.

For people who spend time outdoors, one practical reality is worth preparing for: it may become more common to come across sick or dead birds on beaches and around waterways. Distressing to see, and knowing what to do — and what not to do — is critical.

In a July 2026 webinar, a group of Australia’s leading science and conservation organisations — the Australian Marine Conservation Society, Biodiversity Council, BirdLife Australia, Doherty Institute, Invasive Species Council and Wildlife Health Australia — discussed the global impact of H5 bird flu, the risks to Australia’s wildlife, and what is needed to strengthen the national response.

 

What is being done to protect Australia’s wildlife?

The Threatened Species Commissioner has pointed to habitat enhancement, water management, and the control of invasive predators — feral pigs, foxes and feral cats — as ways to give native species the best chance of withstanding the virus when it reaches them. Healthy habitats and strong populations will help wildlife absorb this shock.

Governments and conservation groups are working out which species are most at risk, looking at susceptibility — how likely a population is to encounter the virus, become infected and die — and vulnerability — how badly infection would affect the species as a whole, up to the loss of an entire population. A species that scores high on both, such as a scavenger surviving in small numbers at a single site, is a priority for action.

The Australian Government has committed $113 million, which according to the Biodiversity Council comprises $43.9 million for national coordination, surveillance and biosecurity; $47.1 million to identify the most at-risk species and sites and develop response plans. A further $11.2 million has been promised in the 2026–27 Budget; and $22.1 million to expand pandemic-flu vaccine and antiviral stocks in the National Medical Stockpile. Conservation organisations argue that more is needed to protect wildlife specifically, and are calling for an additional $200 million wildlife resilience fund — the campaign being promoted by BirdLife Australia and the Invasive Species Council.

Could vaccination protect our wildlife?

Vaccination cannot stop H5 bird flu spreading through wildlife. What it could do is prevent an outbreak from wiping out a small, at-risk population in one place.

New Zealand shows what preparation looks like. Its Department of Conservation spent two years trialling vaccination in its most endangered birds before the virus arrived — researching how different species tolerated the vaccine and what doses they needed. That work meant a targeted program was ready to go: 196 of 300 targeted birds across six species have now been vaccinated, all from populations small enough and closely enough managed — GPS tracked, health monitored, often on offshore islands — that individuals can be found, given a booster and followed up. New Zealand recorded its first case in a native bird in July 2026.

Elsewhere, the United States vaccinated 207 California condors by October 2024, after the virus killed 21 of the critically endangered birds. France has trialled a vaccine in wild king penguin chicks on the sub-Antarctic island of Crozet, which produced strong virus-neutralising antibodies with no adverse effects detected.

Australia’s rollout has now begun. In August 2026 the federal government announced a national vaccination program for the native birds most at risk, with around 1,500 vials secured at a cost of about $2 million. States and territories are managing the rollout. Captive birds are the priority, ranked by how vulnerable the species is and how likely it is to encounter the virus; wild birds will be vaccinated where that is possible. Doses vary with the size of the bird, and the government says more vaccine can be secured if needed.

Agriculture Minister Julie Collins said the spread through wild birds cannot be stopped, but action can be taken to protect the species most at risk, and vaccination is now part of that response. Australia’s Chief Veterinary Officer, Dr Beth Cookson, was equally clear that it is not a standalone solution: biosecurity remains essential, and the program rests on 18 months of work on safety and efficacy data.

Tasmania has named the first species. Up to 350 captive orange-bellied parrots at the Five Mile Beach facility — central to the national breeding program — will be vaccinated once Commonwealth approvals come through, ahead of a scheduled release to the wild. South Australia is working with Zoos South Australia and Cleland Wildlife Park to assess which captive threatened species should be prioritised.

Triage is unavoidable. Little penguins are expected to be affected around Tasmania, but they are not a vaccination priority: they are widely distributed and not threatened, so the doses go to species with less margin. The policy also does not cover non-avian species, so seals and sea lions sit outside it.

That focus on captive birds is not timidity, it is arithmetic. Most H5 vaccines need two doses, and most wild animals are hard to catch once, let alone recapture for a booster. Dr Kirsty Short of the University of Queensland says the practical target is captive animals at risk because they are endangered, rather than field vaccination of wild populations, and that testing a vaccine on a wild population takes around seven months from start to finish. Associate Professor Mohammed Alsharifi of the University of Adelaide, an influenza vaccination expert, says it is the right approach for conserving these species: the virus may yet mutate, but building immunity against the strain now circulating is worth doing.

Dr Jane Younger, of the Institute for Marine and Antarctic Studies at the University of Tasmania, argues Australia should begin targeted vaccination of threatened birds now, and develop a strategy for seals and sea lions rather than waiting until thousands are dead. She notes there is no bird flu vaccine designed for marine mammals, though a United States trial found a vaccine developed for cattle was safe in northern elephant seals and produced measurable antibodies. Vaccination is not a silver bullet, she says, but when a disease can undo years of conservation work in weeks, the choice is between an unmanaged catastrophe and a closely tracked outbreak met with stronger surveillance, biosecurity and preparation.

For wildlife carers and people who work with birds

Wildlife organisations are expected to support early reporting and surveillance, maintain sound biosecurity, keep themselves and their communities safe, and help raise public awareness. Within that, your own biosecurity matters — both for the animals in your care and for the wild populations around you. General guidance includes:

• Have a biosecurity plan in place for your site or service.
• Keep sick or injured wild birds in care separate from any pet birds or other animals.
• Keep aviaries, bedding and handling equipment clean, and disinfect between animals.
• Know the signs of H5 bird flu, how it spreads, and how to prepare your property.
• Speak to the Emergency Animal Disease 24-hour hotline on 1800 675 888 before disposing of any dead bird — requirements vary between states and situations. You will be connected to an officer in your area.

References

Updated 23 August 2026 — reviewed by Maria Arnold, BSc (Hons), ANU — Founder, Perfect Pets. This page covers a developing situation and the information may change — please check the official sources listed above for the current status.  If you believe any information is out of date, please contact us.