Are Kiwi Birds Endangered? Threats, Numbers and Conservation

What is the conservation status of each kiwi species?

All five kiwi live only in New Zealand. Their status on the IUCN Red List, and rough population estimates, are shown below. Counts are approximate, because kiwi are nocturnal and hard to survey.

Taken together, Save the Kiwi estimates roughly 68,000 kiwi remain. Before people arrived, there were probably millions. The great spotted kiwi alone is thought to have declined by around 90 percent since 1900.

Why are kiwi at risk?

Kiwi evolved in a land without ground-hunting mammals. Before humans arrived, New Zealand’s only native land mammals were bats, so kiwi had no defenses suited to agile mammal predators. They sleep in burrows, have a strong scent and nest on the ground.

The main threats today are:

• Stoats. Introduced in the 1880s to control rabbits, stoats are responsible for about half of kiwi chick deaths in many areas. The story is told in Why are stoats a problem in New Zealand?
• Cats also kill chicks, especially near towns and farms.
• Dogs are the biggest killers of adult kiwi. Dogs find the strong smell of kiwi easy to follow, and one roaming dog can wipe out a local population.
• Ferrets and possums kill adults or take eggs.
• Cars, badly set traps and habitat loss add to the toll, and small, isolated populations face inbreeding.

Chicks are the weak point. Young kiwi stay vulnerable to stoats until they weigh about 1–1.2 kg (2.2–2.6 lb). In unmanaged areas only around 5–10 percent of chicks survive to adulthood.

Why don’t kiwi populations recover quickly?

Kiwi breed slowly. Each female lays only one or two very large eggs per clutch, and the eggs take about two to three months to hatch, as explained in How big is a kiwi egg? Females usually start breeding at three to five years old.

On the other hand, adult kiwi are long-lived. Where predators are kept low, adults can live for 20 years or more, which gives a population time to recover once chicks start surviving. In some parts of Northland, though, dogs and cars cut the average adult lifespan to around 14 years.

How is New Zealand protecting kiwi?

Kiwi conservation is one of New Zealand’s largest wildlife efforts, led by the Department of Conservation (DOC), the charity Save the Kiwi, Maori tribes (iwi), and hundreds of community groups.

Operation Nest Egg. Eggs or young chicks are taken from the wild, hatched and raised in captivity or in predator-free creches, and returned once they weigh about 1.2 kg (2.6 lb). An Operation Nest Egg chick has about a 65 percent chance of reaching adulthood, compared with about 5 percent for a chick left in unprotected forest.

Predator control. Large networks of traps and other predator control protect kiwi in many forests. In 2000, DOC set up five kiwi sanctuaries: Whangarei, Moehau (Coromandel) and Tongariro in the North Island, and Okarito and Haast in the South Island.

Safe islands and fenced sanctuaries. Kiwi have been moved to predator-free islands and to sanctuaries such as Zealandia in Wellington and Sanctuary Mountain Maungatautari in Waikato. The little spotted kiwi survived only because a few birds were moved to Kapiti Island in the early 1900s; the island now holds around 1,200 of them.

Dog aversion training. Owners in kiwi areas can train their dogs to avoid the smell and sound of kiwi, and many kiwi areas restrict dogs altogether.

Is kiwi conservation working?

Yes, where it is done. In 2017 the IUCN moved two species, the North Island brown kiwi and the rowi, from Endangered to Vulnerable. The rowi has grown from about 160 birds in the mid-1990s to around 600, and the little spotted kiwi is increasing on its island refuges.

The challenge is scale. As of 2018, over 70 percent of kiwi populations were unmanaged, and in those areas numbers continue to fall. The national Kiwi Recovery Plan aims to turn this decline into steady growth, and Save the Kiwi has set a goal of 100,000 kiwi.

What is Predator Free 2050?

Predator Free 2050 is a New Zealand government goal, announced in 2016, to remove three groups of introduced predators from the whole country by 2050: rats, possums and mustelids, which include the stoat, ferret and weasel. Large landscape projects are testing whether predators can be removed and kept out of entire peninsulas and islands.

If it succeeds, it would transform the outlook for kiwi and many other native birds. Cats and dogs are not on the target list, so responsible pet ownership remains important in kiwi country.

How you can help kiwi

Visitors to New Zealand can help by keeping dogs on a lead or away from kiwi areas, driving carefully at night where kiwi warning signs are posted and supporting sanctuaries and nocturnal kiwi houses that fund conservation. To learn more about the most common species, see our profile of the North Island brown kiwi, and compare kiwi with other birds that cannot fly in flightless birds.