Desmoulin’s whorl snail

This incredible photograph shows one of the rarest snails in Britain and now a new partnership is working to secure its future.

Around just two millimetres in size, Desmoulin’s whorl snail is one of the UK’s tiniest and most remarkable wetland species and has been found at just two sites in Wiltshire, in Warminster and Pewsey.

Its existence in rare and fragile wetland and riparian habitats is a powerful indicator of healthy wetlands, say experts, who are not revealing the location to protect the species.

However, the tiny snails are in fragmented populations, less able to interbreed and move to unoccupied good habitat which means the species will continue to decline if nothing is done.

The new initiative by Longleat, in partnership with Wiltshire Wildlife Trust, and funded through Natural England’s Species Recovery Programme will combine conservation breeding, habitat restoration, and reintroduction to support and strengthen the existing populations.  

Once found throughout the Hampshire Avon catchment, the species now occurs only in small pockets of wetland and riverbanks in  calcareous (chalk) regions.

Dr Tom Lewis, Longleat’s Head of Conservation and Research, said: “We have an opportunity to make a real difference to a special species that is found right on our doorstep. The wetland habitats in which it lives have historically been lost, as we chased higher agricultural productivity. Creating space for one of our wetlands' smallest residents also creates space for others, so we’re excited to get started.

“This project will restore critical wetland and riparian habitats in Wiltshire and establish a conservation breeding centre for the species. Together, these two approaches will provide more habitat for the species and create a sustainable source of snails for reintroduction. We are delighted to be working with Wiltshire Wildlife Trust on this exciting conservation project to protect a species for the future.”

Alice Eley, Head of Fresh Water at Wiltshire Wildlife Trust, added: “We were delighted to find two populations of the previously unrecorded Desmoulin’s whorl snail in 2025 in Warminster and Pewsey. Protecting a species that is only two millimetres long comes with challenges, especially when the delicate wetlands they rely on are facing extreme pressure from climate change and changing land use. Wiltshire Wildlife Trust are very excited to be launching a project with Longleat where we look to increase the numbers of the snails to actively reverse the decline whilst simultaneously creating resilient, healthy habitats where this tiny snail can thrive” 

Another challenge is that no one has ever bred the species in captivity, so the team will be learning everything from scratch. This means the team will be learning important lessons about the species biology, which could then help its conservation in the wild.  

Dr Tom added: “For any challenging conservation project, you need the best people, and we’ve brought together an incredible team. Using the experience of our in-house team for conservation breeding, working with Wiltshire Wildlife Trust on habitat restoration, and advised by species experts, we have given ourselves the best chance to be successful in conserving a very challenging species.”  

Alice said: “The threats facing the Desmoulin’s Whorl Snail - from shifting water tables to habitat loss - are indicative of how vulnerable our county’s wetlands are. That’s what makes this partnership so special and vital; we are taking innovative action to safeguard rare species and their habitats.” 

Nicky Needham, Head of Species Management and Conservation at the British and Irish Association of Zoos and Aquariums (BIAZA), congratulated Longleat: “Winning this funding is testament to the conservation leadership of Longleat. Most people might think about rhinos or lions when they think of the safari, but real, impactful work, is going on to save some of the smallest and most overlooked species here in Britain. From tiny Desmoulin’s whorl snails to towering giraffes, nature needs us all more than ever and the UK’s zoos are providing a fundamental part of that effort.”