Where Do Tuataras Live? New Zealand's Predator-Free Islands

Tuatara once lived all over New Zealand

The tuatara is native to New Zealand and nowhere else. Bones found in caves, sand dunes and old Māori middens show that it once lived across both the North and South Islands.

Its decline began with the arrival of people. The Polynesian rat, or kiore, came with the first settlers and ate tuatara eggs and hatchlings. Because tuatara breed so slowly, they could not make up for the losses, and they had largely vanished from the mainland before European settlers arrived. Later, Norway rats, ship rats, mice, cats and stoats made the mainland even less safe. New Zealand’s introduced predators are described in Why are stoats a problem in New Zealand?

The island strongholds

For more than a century, wild tuatara survived only on about 32 islands. Most lie off the northeast coast of the North Island, in groups such as the Hen and Chickens Islands, the Mercury Islands, Cuvier Island, the Alderman Islands and Hauturu (Little Barrier Island). The others are in Cook Strait and the Marlborough Sounds, between the North and South Islands.

The biggest population lives on Takapourewa (Stephens Island) in Cook Strait, where tuatara number in the tens of thousands. North Brother Island, also in Cook Strait, is home to a distinct, smaller and olive-brown form of only a few hundred animals, once thought to be a separate species.

Island life is not easy. Many of these islands are steep, rocky and battered by wind, with stunted coastal forest and scrub of salt-tolerant plants. The climate is cool and damp, with air temperatures that rarely rise above about 21 °C (70 °F), which suits a reptile that can stay active at about 5 °C (41 °F) and can die if it overheats.

Life in a seabird burrow

Most tuatara islands are packed with burrowing seabirds, such as fairy prions, petrels and shearwaters. These birds dig deep burrows in the soil to raise their chicks, and tuatara move into them as daytime shelters or dig their own nearby. A tuatara and a seabird may even use the same burrow during the nesting season.

The arrangement benefits the tuatara in several ways. The burrows give shelter from heat and cold, and the birds’ droppings fertilize the soil, supporting large numbers of beetles, wētā, spiders and other invertebrates, the tuatara’s main prey. The relationship is not entirely friendly, though. Tuatara also eat seabird eggs and chicks, and on some islands fairy prion chicks are an important food in summer.

Why rats decide where tuatara can live

Rats are the single biggest reason tuatara survive only where they do. On islands with kiore, adult tuatara could hang on for decades, but almost no young survived, and populations slowly aged and dwindled. Over the past century, about a quarter of the separate tuatara populations died out.

Since about 1990, conservation teams have turned this around by removing rats from tuatara islands. On Stanley, Red Mercury and Cuvier Islands, tuatara were taken into captivity in 1990 and 1991 while rats were eradicated, then returned along with young bred in captivity. On Hauturu, only eight tuatara were found in 1991–92; their eggs were hatched at Victoria University of Wellington, and the young were released in 2006 after the island was cleared of rats. On several islands of the Hen and Chickens group, young tuatara reappeared after rats were removed in the 1990s.

Back on the mainland: fenced sanctuaries

Between 1995 and 2020, tuatara were moved to 14 islands and 5 mainland sanctuaries. The most famous release was at Zealandia, a sanctuary in a Wellington valley surrounded by a predator-proof fence. Seventy tuatara from Takapourewa were released there in December 2005, followed by 130 more in 2007. In late 2008 workers found a tuatara nest, and in 2009 a hatchling was seen, thought to be the first tuatara bred in the wild on the North Island mainland in more than 200 years.

Other fenced sanctuaries have followed, including the Orokonui Ecosanctuary near Dunedin in the South Island, which received tuatara in 2009. Further moves to islands and sanctuaries continue, as new sites are cleared of predators.

Where can you see a tuatara?

Most natural tuatara islands are closed to the public, and landing without a permit is not allowed, to keep out rats, seeds and disease. A few sites let visitors see tuatara living free:

• Zealandia, Wellington: tuatara live free inside the fence and may be seen basking on sunny days.
• Tiritiri Matangi Island, near Auckland: 60 tuatara were released in 2003 and are occasionally seen by visitors.
• Matiu/Somes Island, Wellington Harbour: Brothers Island tuatara were released in 1998.

Visitors to these islands are asked to check their bags, shoes and boats for rodents, insects and seeds before landing. Tuatara can also be seen in several New Zealand zoos, wildlife centers and breeding programs, including Henry’s long-time home in Invercargill, featured in How long do tuataras live?

Do tuatara live anywhere outside New Zealand?

Not in the wild. The tuatara is listed on CITES Appendix I, so commercial international trade is banned, and New Zealand protects it absolutely under its Wildlife Act. A small number live in zoos abroad under special permits. San Diego Zoo holds Brothers Island tuatara, and in 2016 Chester Zoo in England announced the first tuatara bred in captivity outside New Zealand.