Chester Zoo conservationists have successfully reintroduced 300 captive-bred Madeiran land snails to a remote rock on Bugio Island, part of Portugal's Madeira archipelago, after the species was nearly wiped out in the wild. The rescue matters because just 21 of the tiny snails were originally found clinging to the rock, believed to be the last survivors of their kind, making the breeding programme critical to preventing the species' extinction. The Madeira government had specifically asked Chester Zoo's experts to lead the conservation effort.

Getting the snails back to their natural habitat proved extremely difficult, as there is no jetty on the island and conservationists had to jump into rough seas, climb a cliff face in the dark wearing helmets and harnesses, and locate rock crevices where the snails could be safely released. The snails measure no more than 8mm long but play an important ecological role by eating vegetation and enriching the soil; their progress will now be monitored as they resettle into the wild.