Conservationists have launched a rescue mission after two species of snail thought to have been extinct for more than 100 years were discovered on a remote island in the Atlantic Ocean.
The Desertas Islands land snails had not been recorded living for more than 100 years, until experts rediscovered populations of two species of the snail on the Madeira Archipelago.
The snails are now part of a conservation recovery plan supported by the International Union for the Conservation of Nature (IUCN), in which specialists at Chester Zoo and Bristol Zoological Society are leading a final attempt to save the species by expanding their numbers.
Special breeding centres have been created by invertebrate specialists at both charity zoos to replicate the prime conditions needed for the snails to reproduce.
Chester Zoo’s curator of lower vertebrates and invertebrates, Dr Gerardo Garcia, said: “These snails had not been seen for decades and were thought to have gone extinct, so urgent action was required when only a handful of these special snails were found clinging on to survival.
“Starting with just 20 of the last known individuals on the planet from each group, there was a lot of pressure to find answers quickly.
“But with the technical knowledge, scientific underpinning and the skills developed here at the zoo with other highly endangered invertebrates, our team was able to develop the ideal breeding conditions.
“Now, with more than 1,200 safely in our care, we can say that we have prevented two magnificent species from becoming extinct, which is an incredible achievement.”
Chester Zoo now has more than 1,200 of the tiny snails in its care as both species, Discula lyelliana and Geomitra grabhami, have been officially listed as critically endangered by the IUCN.
The next steps in the recovery process involve looking to build “an international breeding programme that provides a sustainable future for the species”, Dr Garcia added.
Experts also hope to be able to return many of the snails back to the Desertas Islands and new locations once work is completed to “restore habitat and remove the invasive species that have devastated the islands”.
The Desertas Islands are now protected nature reserves under Portuguese and European law.
Mark Bushell, curator of invertebrates at Bristol Zoo, said it was a “huge privilege” to play a role in the preservation of the snails.
“These snails are a vital part of the natural ecosystem on the Desertas Islands and are found nowhere else on the planet, so to be able to play a part in securing the future of these species is a huge privilege.
“We will draw on the wealth of knowledge and experience that we have from decades spent breeding and caring for a range of other critically endangered snail species, and use this to ensure this species is given the best possible chance for the future.”
The conservation plan will provide “the blueprint for increasing conservation work even more over the next 10 years,” Chester Zoo’s animal and plant director, Mike Jordan, added.