Scientific name: Partula faba
Country: French Polynesia, Raiatea
Diet: Detritus, decomposing plant material
Food & feeding: Herbivore
Habitats: Tropical rainforest
Conservation status: Extinct in the wild
Relatives: Giant clam, octopus, giant African land snail
Description: Polynesian tree snails are endemic to many of the volcanic islands of the South Pacific. They have an enormous geographical range, from Belau, east of the Philippines, to the Marquesas Islands. Partula fabawas first discovered in 1769 by Joseph Banks and others during the first voyage of the endeavour. It is a small spiral-shelled land snail and is around 20 mm in length. Like other snails, they can retract their bodies inside their shells. They move around the trees and plants by using waves of muscular activity in their single foot. The foot glides over the surface of leaves on a layer of slime that is produced by a gland at the front end of the foot. They have dozens of tiny teeth, embedded in a strip of flesh in the mouth called the radula. The radula acts like a file, grinding their food from the surface of plant material as they go.
Lifestyle: They spend their time grazing decomposing plant material in the forests of the small French Polynesian island of Raiatea, found to the south-west of Tahiti. They are most active at night and after rain.
Growing up: All species of Partula are ovoviviparous with 1-2 mm newborn growing to adulthood in as little as 3-6 months
Conservation news: The story of Polynesian tree snails, such as the partula, is a sad one. African land snails were introduced to the islands as a source of food for the local people, but they soon escaped and started eating crops. In 1974 , in an effort to control the land snails, a smaller predatory species of snail was introduced; Euglandina rosea. This species started to feed on the native Polynesian tree snails. Before long, many species of Polynesian tree snails became extinct. Out of an original 125 species in 3 genera (including Partula), 50 species are now extinct in the wild, and 24 survive in captivity.
Five species of Polynesian tree snail are being kept in Bugworld at Bristol Zoo Gardens, four of which are extinct in the wild and one critically endangered. Partula faba can only be found in Bugworld and the global population is under 100 although it is rising with recent breeding success.
In the islands of French Polynesia, dozens of different species of tree snail used to live alongside one another. Some lived only in single valleys, others lived in a number of valleys on a single island.