Carnivorous snails Most of the snailspecies are planteaters as a lot of gardeners can confirm,although a lot of snails prefer soft,rotting plantmaterial.Occasionaly when they come upon a dead animal snails might nibble on it.Some snails and especially slugs who live most of the time in the ground eat worms. There are a few snailspecies however who predate on other snails.One of the most well known is Euglandina Rosea(Ferussac,1821),the Rosy Wolfsnail.It is a native of Florida,but has spread to other Southern States like Alabama,Georgia,Louisiana, Texas and South-Carolina. In 1955 they were introduced in Hawaii to control the Giant African landsnails that caused a lot of damage to agricultural crops.Although they ate some of the African landsnails other ,much smaller,snails became their prey too. Some years later Euglandina rosea was also introduced in The Philippines,New Guinea and other islands in the region. The Giant African landsnails were also becoming a problem in French Polynesia where they were being kept as a foodsource in the 1960ís and early 1970ís. When farmers stopped the snails were released in the wild.With no natural enemies they reproduced rapidly and became a danger to crops.In 1977 Euglandina rosea was introduced to Moorea to cope with this problem.Even though they succeeded in reducing the African Landsnail population,other snailspecies such as the Partula snails were eaten too.The Partula snails were a much easier prey than the big African snails. Scientists faced with the possible extinction of the Partula snails removed some of the population and started a breeding program in captivity.Now there are some Partula snailcolonies in a few Zoos.A 1987 expedition to Moorea failed to find a single living Partula snail. More on Euglandina rosea here.
Another well known carnivorous snailspecies is Rumina decollata(Linnaeus,1758)and comes from the Mediterranean.This species has also been introduced to other areas like North-America, were it lives in California to Florida and along the Atlantic coast north to Pennsylvania. Even though they eat plants people say their preying on Brown Garden Snails(Helix aspersa)outweigh the possible damage. More on Rumina decollata here.
A third carnivorous snailspecies living in North-America and Canada is Haplotrema concavum(Say,1821). It is distributed from South-Canada to the Gulfstates and west to Nebraska and Oklahoma.It also lives in some counties in Florida. Hubrecht(1985)says the snail feed more on shells than on living snails. More on Haplotrema concavum here.