Are the European snails, Theba pisana (Müller, 1774) (Helicidae), Cernuella virgata (da Costa, 1778) and Cochlicella acuta (Müller, 1774) (Hygromiidae) attracted by potential food odours?

White snails, Cernuella virgata and Theba pisana, and the conical snail Cochlicella acuta, are introduced pests of grain crops and pastures throughout much of southern Australia. All are native to Europe and, in particular, widespread throughout the western Mediterranean. The snails are principally regarded as pests in Australia because they foul grain harvests when aestivating on the heads and stalks of crops. Molluscicide baits are commonly used to control the pests. These baits are usually based on a bran or pasta formulation with metaldehyde as the pesticide ingredient. However, the baits are not strongly attractive as food sources for the snails. Their cost-effectiveness could be enhanced if more attractive formulations were developed. We therefore explored the possibility that other potential food sources/attractants could be incorporated into baits to increase their effectiveness against white and conical snails. The snails were assessed for preferential attraction towards odours elicited from 21 potential food attractants offered in olfactometers, with water as a control. The common, brown garden snail (Cornu aspersum), with its known attraction to carrot, was used to verify the validity of the olfactometer design. We were unable to identify any food items that elicited strong preferences in the white and conical snails. A few positive responses, and one negative, were obtained but these could well have occurred by chance, given the large number of tests that were completed. It seems most likely that white and conical snails are not directly attracted to food in their environment, but find it by random encounter.

► Exotic snails are major pests of cereal crops in southern Australia. ► Chemical, cultural and biological control have been attempted with limited success. ► Bait performance could perhaps be improved by adding feeding stimulants. ► However, the snails showed little attraction to a wide range of potential stimulants.