Euglandina rosea (original) (raw)

Since their first introduction to tropical islands in the 1800s the giant African land snails Lissachatina fulica (=Achatina fulica) and Achatina immaculata have been regarded as serious agricultural pests. These two species, originating from East Africa and Madagascar, have now been introduced to at least 27 countries, largely accidentally. Extremely high densities of these species occurred on several Pacific islands in the 1940-50s. The effects of the population explosions prompted much interest in methods of control, including hand collection, chemical and biological control. The latter has been the most widely used option. This included a variety of taxa from flatworms to reptiles, including predatory snails.

The results of these introductions have been variable: some failed, others established but remained rare and in some places rapid expansion occurred. The established introductions did not cause the expected declines in Achatina populations and in several cases Euglandina introductions have been blamed for the rapid extinction of many native molluscs (especially in Hawaii and French Polynesia). Two families of snail have been particularly badly hit: the Partulidae and Achatinellidae. In the Partulidae sine 1978 Euglandina has been directly responsible for the complete extinction of 52 species, a further 11 survive only in captivity and another 35 are at serious risk of extinction. In the Achatinellidae the introductions in the 1950s have led to 27 complete extinctions, 27 species extinct in the wild and 22 on the edge of extinction. Many other species have probably been lost without being noticed.

In order to find ways of controlling the threat Euglandina poses to many snail faunas the ecology of the predator has been studied by several research groups, although additional studies are needed: