How this remarkable sea bird became the harbinger of bad news

Tuesday, 21 July 2026

A brown skua found at Petone Beach on July 10 became New Zealand's first confirmed case of H5N1 bird flu after treatment at Wellington Zoo.

H5N1 bird flu has killed millions of birds and mammals globally, with mortality rates reaching 75% in some sea mammal populations.

A second H5N1 case was confirmed in a kāhu found near Carterton, suggesting potential domestic transmission between animals in New Zealand.

How did bird flu end up in New Zealand, and what could happen next? Glenn McConnell reports.

When a lone brown skua was found in Petone, it, luckily, caught someone’s attention.

That seafaring bird is rarely seen on New Zealand’s two main islands, and it’s extremely unusual for it to hang around in Wellington harbour. It prefers the Chatham Islands, uninhabited islands in the sub-Antarctic, or even just the middle of an ocean.

This bird’s rare visit to Petone Beach, a popular spot for Wellingtonians to walk their dogs, caused enough of a scene for one person to notice that something was amiss. This black-billed, beady-eyed critter was not well.

It was found on July 10. After being taken to Wellington Zoo’s animal hospital, The Nest, that bird became the first confirmed New Zealand case of H5N1 bird flu last Wednesday, about a week after it first arrived in Wellington.

Since it was discovered in 2020, this variant of H5N1 has killed millions of birds and mammals across the globe. It is especially lethal for poultry, killing entire flocks, and can infect mammals, such as sea lions and seals, with a mortality rate of up to 75% in some sea mammal populations.

Its arrival in New Zealand last week was not unexpected. The virus has infected pretty much ever other country, and even Antarctica.

“It’s inevitable,” said Biosecurity Minister Andrew Hoggard, on Wednesday evening, during a press conference announcing the arrival of H5N1 to Aotearoa.

AI-fuelled conspiracy theories

But the arrival of this sick brown skua did spark questions from the public. Online, social media comment threads flared with questions and conspiracy. Some wrote to the Government, saying their conversations with AI chatbots had informed them there was no way a poorly brown skua could have flown all the way to New Zealand. Fuelled by faulty AI-fuelled theories, conspirators speculated that someone must have dropped off the bird in New Zealand.

It was, experts agree, somewhat unusual. But the bird’s arrival was also completely reasonable, and completely plausible, says associate professor Phil Battley, a Massey University biologist who has studied seabirds around the Southern Hemisphere.

A keen bird watcher himself, Battley has seen two brown skua in the lower North Island before.

“They do turn up, they turn up more in winter in other times of the year - when they’re not breeding - so there’s nothing too unusual about it. It’s just not a common sighting.

“The last time I saw one, I was sitting at Foxton Beach with my family when my kids were little, and one just flew past, most unexpectedly,” he recalls.

Brown skuas do breed on land. There’s a population that breed at the Chatham Islands, and Battley says there could be some breeding at the southern tip of Stewart Island.

It is possible that this individual bird, found sick in Petone, had decided to seek shelter because it was unwell.

“If a bird was sick, it certainly would be easier for the sick bird to hang out on a beach than float on an ocean. But I’m not sure how we would ever know for sure, because the chance of seeing a sick bird at sea, and knowing it’s a sick bird, would be quite slight,” Battley says.

It’s common, following storms, for weaker seabirds to end up on land.

“Sick birds do turn up on beaches. For albatrosses and petrels, the ones that often have to go to rehabilitation it’s normally the result of a storm. When they can’t feed for four of five days, they get exhausted,” he says.

Sub-Antarctic wildlife almost completely wiped out

It was also a brown skua, as well as a giant petrel, which first alerted Australia to the presence of H5N1 bird flu on its shores.

Skuas and giant petrels fly around oceans when they’re not breeding, in winter. They hunt at sea, but also scavenge and eat dead birds and mammals.

In the sub-Antarctic, many of those birds and mammals are dying because of H5N1.

In June, the Australian Antarctic Program reported devastating impacts of the virus after an expedition to Heard Island, an Australian territory which sits about 4000km from Perth.

The highly contagious bird flu had killed almost every baby elephant seal on the remote island.

“Analysis of data collected in October estimated average pup mortality was 76% in the final surveys and as high as 97% in one area,” the report said.

They estimated 17,000 seal pups were born, and only 4000 survived.

Race to vaccinate native birds

The Department of Conservation (DOC) has started a targeted vaccination programme for 300, mostly captive, birds. Breeding pairs from takahē, kākāpō, kakī (black stilt), tūturuatu (shore plover), and kākāriki populations are eligible for vaccination.

To be effective, each bird needs to receive two doses of the vaccine - meaning it it would be difficult to vaccinate wild populations.

On Thursday night, the Government’s chief veterinary officer, Mary van Andel, granted DOC approval to vaccinate other species.

“A final list of species has deliberately not been fixed. This gives DOC the flexibility to respond to new detections, emerging risks, and what our experts are seeing on the ground as we build a clearer understanding of how the virus may affect New Zealand’s wildlife,” Conservation Minister Tama Potaka said, in a statement.

Given New Zealand birds haven’t faced this strain of avian influenza before, conservationists don’t know which species will be worst impacted. Almost 100 kākāpo are being vaccinated, in part because they’re easy to catch - but also because they live on islands where can easily catch bird flu from seabirds.

Officials from the department did not respond to Stuff’s requests for an interview for this article.

Second case raises prospect of fast-growing contagion

By the time that new approval had been communicated, a second case of bird flu had already been confirmed.

The second case was identified in a native bird. A kāhu, near Carterton, an inland town north of Wellington, was confirmed on Friday to have H5N1.

Kāhu, like brown skua, scavenge dead meat. But unlike the brown skua, kāhu don’t fly across oceans. They live on the mainland.

Professor Jemma Geoghegan, a virologist at the University of Otago, said the latest case suggested domestic transmission between animals in New Zealand.

“It suggests that potentially there’s a source - a reservoir that is the source of these infections,” she said.

She said there could be a small population of infected birds dying and being scavenged by other birds.

Other experts who Stuff spoke to agreed.

Professor Nigel French, an epidemiologist at Massey University’s school of veterinary science, said it was “quite likely” the kāhu caught bird flu locally.

“That means there is, potentially, a pocket of infection that has been undetected so far,” he said.

That infection could have come from a dead sea bird, like a brown skua that had come to land after being infected at sea, or he said it could be another source.

Battley, the biologist, says this second confirmed infection means the virus may have already spread to multiple species.

Given the kāhu was found near Carterton, he said that raised a possibility it caught the disease from a lake.

“If it was from Lake Wairarapa, or a farm somewhere …. then that could spread quite widely. Waterfowl overseas have been very heavily affected,” he says.

Time will tell, over the next few weeks, how widespread bird flu is.