These pea-sized snails were considered extinct for 100 years - now they're being released into the wild

A species of tiny snail has been brought back from the brink of extinction.

The Desertas Island land snails were believed to have disappeared altogether for 100 years, but experts have managed to breed them in captivity after discovering tiny populations on an isolated island called Desertas Grande in the Madeira Archipelago, Portugal.

Now more than 1,300 of the critically endangered snails are being released into the wild on the nearby island of Bugio.

The rescue effort began when a team of conservationists discovered two species of the snail surviving on the rocky cliffs of Desertas Grande.

Fewer than 200 individual snails were found in each population.

They were believed to be the last of their kind so the conservationists brought them to zoos in the UK and France as part of efforts to save the species.

Sixty of the pea-sized snails were flown to Chester Zoo, where experts began a unique breeding programme to boost their numbers.

Both of the species were successfully bred in captivity for the first time ever.

Dr Gerardo Garcia, Chester Zoo's head of ectotherms, said: "When the snails first arrived in Chester the very future of the species was in our hands.

"As a zoo conservation community, we knew nothing about them. They'd never been in human care before and we had to start from a blank piece of paper and try to figure out what makes them tick - how to care for them, how to create an environment in which they could flourish, and how to encourage them to breed."

He said the snails had been "on the edge of extinction" but now they have a "chance of making a comeback".

The snails had originally been all but wiped out due to invasive goats, rats and mice.

Experts chose to relocate them to Bugio island as they would be less at risk from these threats.

Each of the snails has been individually marked with a tiny amount of infra-red paint so they can be carefully monitored.

(c) Sky News 2024: These pea-sized snails were considered extinct for 100 years - now they're being released