New Zealand is Racing to Vaccinate Its Endangered Birds Against Bird Flu

It’s not easy to vaccinate New Zealand’s rare birds. It can sometimes involve a journey to a remote, windswept island or deep forest. Then researchers must locate the bird, which could be camouflaged on the ground eating berries or high up a tree. Next, they must capture it and administer the vaccine. And a few months later, they do it all again when the bird needs its booster shot.

But for New Zealand’s Department of Conservation staff, it is a matter of protecting the country’s endangered endemic wildlife against the deadly H5N1 bird flu.

New Zealand officials knew it was only a matter of time before the disease arrived in the country. As soon as the first case was detected in Australia in June, the department’s staff started pre-emptively vaccinating up to 300 of New Zealand’s rarest and most at-risk birds.

Just weeks later in July, New Zealand confirmed two cases of H5N1 in wild birds in Wellington, the capital.

Ash Murphy, the department’s biosecurity and weeds manager, said that some endemic species — meaning those found naturally in only one place on Earth — were already low.

“Any new threat, like bird flu, can have a pretty devastating impact,” he said.

As part of the plan, 300 birds from five key species — including the kākāpō, the world’s fattest parrot, of which just 235 remain — are being vaccinated first. There are only a handful of each of these species remaining in captive breeding programs or in the wild. The government hopes to complete this phase as soon as possible before moving on to other species.

The vaccination work can be difficult. The kākāpō is found on offshore islands in the deep south. Rangers, using trackers, have to locate the bird (which can climb high up into trees with its strong claws) and catch it. They can also use the opportunity to carry out health checks, Mr. Murphy said.

The authorities have so far vaccinated about 196 birds. Once this phase is complete, another 23 species will be vaccinated — including rare kiwis and the kea, a playful and intelligent bird that is the world’s only alpine parrot.

Many of New Zealand’s birds are flightless, a trait developed because the country was isolated for millions of years and had no ground-dwelling predators like ferrets and rats until humans introduced them. As a result, they evolved to fill gaps left by mammals. Birds hold a special place in the hearts of New Zealanders, who refer to themselves as Kiwis.

Bird flu swept across Europe, Africa and Asia in 2020. In late 2021, it showed up in North America, storming through Canada and the United States. In the fall of 2022, the virus appeared in South America, spreading down to the tip of the continent in mere months.

Thousands of wild birds and mammals — including foxes, cats, sea lions and dolphins — have died after contracting the disease. There have also been rare cases in humans after close contact with birds.

Bird flu is hard to stop, especially if wild migratory birds or animals carry it with them as they travel the globe.

“You can’t block migration pathways in the same way that you could stop trade in animals or animal products, and also the movement of people. So it does represent something quite different to anything else we’ve seen,” said Nigel French, a distinguished professor of infectious disease epidemiology at Massey University in New Zealand.

But scientists have been able to learn from other disease outbreaks, including the coronavirus pandemic, he added.

As a result, the basic practices around controlling disease have improved, including biosecurity barriers, movement restrictions and genomic sequencing to track the origin and spread of the disease. Vaccines have also become more effective.

At Willowbank Wildlife Reserve in Christchurch, staff have been preparing for bird flu for several years, Laura Ashton, the facility’s wildlife operations manager, said in a statement.

This includes installing a shade cloth over selected habitats to deter wild birds; modifying feeding and water stations to reduce access for pests; and stronger biosecurity protocols for animal carers.

So far, four takahē — a flightless bird of which only 500 remain — have been vaccinated at the facility.

Officials said they would not be able to eradicate bird flu, but that it would be a matter of learning to live with it. This week, Australia confirmed the first mass wildlife deaths from the disease in greater crested terns found on an island off South Australia’s coast. Officials have warned more wildlife will be affected.

Mr. Murphy, the biosecurity manager, was “pretty confident” in New Zealand’s plan. But he added that there was uncertainty as to how the disease would affect precious and endemic species.

“It’s a bit of a waiting game to see what happens,” he said.