THEY weigh little more than a gram and are no bigger than three centimetres in length, but Chester Zoo is throwing its weight behind a conservation programme to protect some diminutive animals.

Partula snails are critically endangered and, in some cases, many species are now extinct in the wild.

Chester Zoo is home to three species of Partula – varia, mirabilis and hyalina – and holds up to 70% of the world’s zoo population of these Partula species.

With an excellent track record in breeding the tiny snails, the zoo has now lent its help to a field project aimed at monitoring and studying the snails in the wild.

Invertebrate keeper Karen Entwistle spent two weeks in Tahiti with expert Trevor Coote, surveying Partula populations to assess the situation.

Karen said: “The biggest threat to Partula snails comes from the predatory snail species Euglandina rosea, which was introduced by humans to the islands of the Pacific Ocean.

“Trevor has dedicated his life to monitoring the existence of Partula in the wild and it was an invaluable experience to spend time with him. They were long days, sometimes we were walking for up to eight hours a day, and what is distressing is that in some cases, we would find that entire populations are being, or have been, wiped out.

“However, part of the trip involved working on what will be the Tefaaitit Reserve site. It is hoped that eventually three species of Partula will be released here which would offer some hope for them in the wild.”

Partula snails are named after the Roman goddess of childbirth, Partula, as they are one of the few species of snail to give birth to live young.

They are notoriously slow breeders, having one baby every four to six weeks and live for between two to five years. However Karen said the trip gave her some valuable tips on working with the species back at the zoo.

“Chester has an excellent record when it comes to breeding Partula but this trip did give me more ideas about our husbandry back at the zoo. Potentially there are new things for us to try and I learnt a lot about the best conditions under which to keep our snails. It was a once-in-a-lifetime experience and one I hope to repeat in the future.”

Karen’s trip was funded through the zoo’s Keeper for a Day scheme. Keeper for a Day enables visitors to pay to work alongside the animal teams and in turn raises funds for the zoo’s conservation projects.