Offshore islands have rich biodiversity. They are often home to native species that cannot survive on the mainland because of predators.

Islands provide a unique opportunity to remove predators. They have clear natural boundaries and are mangeable in size. This makes eradication possible using current tools. 

DOC leads predator control work on public conservation land. We also work with tangata whenua and landowners on private land.

Over the past 70 years, DOC has tested different methods to remove predators from islands. In 1960, we achieved the world's first rat-free island on Maria Island.

There are now more than 110 predator-free islands in New Zealand. These islands show that predator removal can succeed and that a predator-free status can be maintained.

DOC responds quickly to pest incursions on islands that are currently predator-free. DOC works with Auckland Council to keep islands predator-free in the Hauraki Gulf/Tīkapa Moana.  

Our recent successes

Maukahuka Pest Free Auckland Island

DOC invested $3 million over three years to study how to remove feral pigs, cats and mice from Auckland Island. At 46,000 hectares, Auckland Island is the fifth largest island in New Zealand. The project is large but achievable.

Maukahuka Pest Free Auckland Island  

Million Dollar Mouse

In 2018, mice were removed from the subantarctic Antipodes Island (2,100 hectares). DOC worked with supporters, the Morgan Foundation, WWFNZ and Island Conservation. This partnership delivered the ‘Million Dollar Mouse’ project and attracted extensive support.

This work has created a safe haven for many native species. These include the endemic Antipodes snipe, pipit and two species of parakeet.

Mice removals

In 2017, mice were removed from Motuareronui/Adele Island. This allowed South Island robins to be reintroduced. The island is now used as a creche for great spotted kiwi/roroa chicks.

In 2019, mice were removed from Te Hoiere/Maud Island. This protects vulnerable species such as Southern striped geckos and the Maud Island frog. It also protects many insects, reptiles and kororoa/little blue penguins.

What's next

The goal is to remove all mammal predators from New Zealand’s uninhabited offshore islands. This is achievable by 2050.

The team is identifying which islands can be made are predator-free and developing a prioritised action plan based on available funding. Investment in research and development is important to improve our ability to defend islands from re-invasion.

The lessons, tools and skills built from this work will help achieve Predator Free 2050 on the mainland.