PREDATION BY THE INTRODUCED CARNIVOROUS SNAIL EUGLANDINA-ROSEA (FERUSSAC) ON ENDEMIC AQUATIC LYMNAEID SNAILS IN HAWAII

Conservation biologists have long been aware of the fact that introduction of generalized carnivores as biological control agents may have negative effects on native species with habitats similar to target species. However, behavioral plasticity of the predator may allow it to extend its activities to previously unutilized habitats resulting in unanticipated environmental problems. Euglandina rosea, a predaceous snail, is known to have serious impacts when introduced to islands with native land snail populations. This carnivorous snail has now been observed in aquatic habitats, raising the possibility that it could also have deleterious effects on populations of endemic freshwater snails. Observations and experiments confirm that E. rosea has, as part of its behavioral repertoire, the ability to seek and capture aquatic snails. These results suggest that the potential for damage to native molluscan faunas by this snail is greater than previously realized.