Once thought lost, a rare snail returns - RZSS

A rare species of Polynesian tree snail once declared Extinct in the Wild has officially been downlisted, thanks to a decades-long conservation programme led by ZSL — the charity behind London Zoo — and its global conservation partners.

The Partula tohiveana snail — wiped out in the wild due to the introduction of predatory carnivorous snails — has now been reclassified from Extinct in the Wild to Critically Endangered by the IUCN Red List, a global assessment of extinction risk, following the success of a reintroduction programme in French Polynesia.

This milestone follows the groundbreaking discovery last year of wild-born adult Partula tohiveana individuals in Moorea, confirming that the species is not only surviving but successfully breeding in its native habitat. The snails were part of carefully managed annual reintroductions led by London Zoo conservationists, in collaboration with the French Polynesian Government, the University of Cambridge, and conservationists at Bristol Zoological Society, Detroit Zoological Society, Marwell Wildlife, Poznan Zoo, Riga Zoo, the Royal Zoological Society of Scotland, Saint Louis Zoo, Sedgwick County Zoo, Whipsnade Zoo, Wild Discovery, Woodland Park Zoo, Wuppertal Zoo and Zoo Schwerin.

ZSL first began breeding Partula snails in the 1980s, after their wild populations were decimated by the introduction of the invasive and carnivorous rosy wolf snail (Euglandina rosea). The dedicated programme saw conservationists care for and breed the species in carefully controlled conditions at London Zoo and zoos across the globe, before large numbers of snails were marked with UV reflective paint and carefully released back into their forest habitats in French Polynesia.

David Field, RZSS CEO, said: “This is an incredible milestone in the story of the Partula tohiveana snail. To take the species from the edge of extinction and boost their population in the wild is a fantastic achievement. With our planet facing a biodiversity crisis, this highlights the crucial and unique role zoos play in wildlife conservation. In our 2030 strategy we pledged to help reverse the decline of 50 species by the end of the decade so we are thrilled to see our efforts to save the Partula tohiveana are a success, thanks to the collaboration of conservation zoos.”