Status 86 species of Partula snail are recognised on the IUCN Redlist. Of these, 51 are Extinct, 11 Extinct in the Wild, 15 Critically Endangered, 2 Endangered, 1 Vulnerable, 1 Least Concern and 5 Data Deficient.
Size Up to 2.5cm
Weight Less than 1g
Gestation 2 weeks
Life span Around 5 years in the wild, up to 10 years in captivity
Partula snails are herbivores and will feed on algae and decaying plant matter. Most foraging and feeding occurs at dusk, through the night, or after rain as this is when they are most active.
These animals are found on islands in the Pacific Ocean, from Palau to the Society Islands in French Polynesia. They can be found in tropical rainforest, mostly within trees. This habitat is ideal for Partula snails as the humidity of the forests helps them to keep moist and prevents them from becoming too dry.
Partula snails are known to live lower in the vegetation when they are young and move higher in the trees as they mature.
Like other land snails, Partula snails are hermaphrodites (have both male and female reproductive organs). They are able to produce both sperm and eggs, and can self-fertilise although cross fertilisation is the norm.
After an elaborate courtship, Partula snails will hold the fertilised egg within their body and then give birth to live young (ovoviviparous). Both partners will give birth to fully-formed shelled offspring, measuring 1 to 2 mm, two weeks after fertilisation. These offspring can reach adulthood 3 to 6 months and are able to breed after this time.
Partula snails will rely on their colouring to act as camouflage to avoid predators. Much like other land snails they will retract into their shell if threatened.
Their main predator is the introduced carnivorous rosy wolf snail (Euglandina rosea).
The main threat to this species is the introduction of non-native snail species. Giant African land snails were introduced to the islands where the partula snails are found, as a source of food. However the giant African land snail soon escaped and began to eat crops and damage banana plantations. In order to control the population of giant African land snails another snail species, the carnivorous rosy wolf snail, was released with the intention that they would feed on the giant African land snail. However this species did not prey on the giant African land snail but on the native partula snails instead, which soon resulted in many species of partula snails becoming extinct.
In order to conserve the remaining species of Partula snail, many were taken in to captivity where captive breeding programmes could be set up. These breeding programmes aim to restore numbers. Monitoring and restoration programs are also being put in place for the remaining wild populations and reserves are being created to protect them.
Partula snails (and other snails) have dozens of tiny ‘teeth’ within a strip of flesh known as the ‘radula’. The radula acts like a file to grind their food from the surface of plants and decaying plant matter.
To move around, snails will use a single ‘foot’. This is covered with a layer of slime that is produced by a gland at the front end of the foot, and they will move around using waves created by the muscles within the foot of the snail.
I am still buzzing from my visit, a fantastic day, with very friendly people and amazing animals, I'm already signed up for the next volunteering day!! Wendy, Southern Co-op, 23rd May 2018