Protecting Powelliphanta: A Sanctuary for New Zealand’s Giant Native Snails

From our 2025 Annual Review:

OneFortyOne New Zealand took a bold step in biodiversity protection by establishing a sanctuary for Powelliphanta hochstetteri consobrina –one of New Zealand’s most endangered native land snails.

Located in the Rai Forests, the sanctuary is a collaboration between OneFortyOne, Ngāti Tama, and the Department of Conservation (DOC), and reflects a growing commitment to conservation within commercial forestry. Powelliphanta snails are among the largest and most distinctive invertebrates in New Zealand.

Known for their vibrant shells and carnivorous diet, these snails can live for decades but face severe threats from habitat loss, climate change, and introduced predators like pigs and rats. Their conservation status is ‘Nationally Critical’, meaning extinction is a real possibility without intervention.

‘When we discovered these rare snails in our estate, we knew we had to take action,’ says Jo Field, Environment Manager, OneFortyOne New Zealand Forests. ‘We’ve installed a predator-proof fence and adjusted our harvesting practices to ensure these special creatures are protected for generations to come.’ The sanctuary not only provides a safe haven but also serves as a research opportunity. DOC’s Powelliphanta specialist Ruth Cole noted, ‘These aren’t your garden variety snails–they’re carnivorous giants that play an important role in forest ecosystems. Seeing a forestry company take proactive steps to protect them is truly encouraging.’ Ngāti Tama, the landowners of the forest estate, are deeply involved in the project through their practice of kaitiakitanga (guardianship).

Dayveen Stephens, Environment Manager, Ngāti Tama, says, “These snails are an important part of our forest ecosystem. This sanctuary allows our whānau to stay connected to endemic species and demonstrates how commercial forestry and conservation can coexist.’

Beyond the sanctuary, we continue to support Indigenous biodiversity across our New Zealand operations. Jo explains, “We’ve recorded sightings of kārearea, kea, kākā, native bats, and Powelliphanta in our forests. Plantation forests provide critical habitat, and we take our responsibilities seriously.’ The establishment of the sanctuary reflects a broader shift in biodiversity management in New Zealand. As Jo puts it, ‘We are all responsible.

Plantation forests have an important role to play in the survival of threatened species’. The Powelliphanta sanctuary is a powerful example of how industry, iwi, and conservation can come together to protect New Zealand’s unique natural heritage