Toward a push–pull strategy against invasive snails using chemical and visual stimuli

Authors: KOSCIOLEK, CEDRIC - Commonwealth Scientific And Industrial Research Organisation (CSIRO); DESURMONT, GAYLORD - European Biological Control Laboratory (EBCL); THOMANN, THIERRY - Csiro European Laboratory; ZAMPROGNA, ALBERTO - Commonwealth Scientific And Industrial Research Organisation (CSIRO); CARON, VALERIE - Commonwealth Scientific And Industrial Research Organisation (CSIRO)

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2024
Publication Date: 5/20/2024
Citation: Kosciolek, C., Desurmont, G., Thomann, T., Zamprogna, A., Caron, V. 2024. Toward a push–pull strategy against invasive snails using chemical and visual stimuli. Scientific Reports. 14:11511. https://doi.org/10.1038/s41598-024-62225-6.
DOI: https://doi.org/10.1038/s41598-024-62225-6

Interpretive Summary: Invasive Mediterranean snails are major pests worldwide and cost $170 million dollars yearly to the grain industry. These snails feed on the ground but climb on vertical supports such a plant stems when summer comes to spend the warmest months of the years in a dormant state, a behavior called estivation. Snails that climb on cereal stalks get harvested and cause grain contamination. Chemical molluscicides are mainly used for snail control but are not fully effective and draw environmental concerns. Here we explore a novel management method named push pull strategy. The goal of the method is to "push" snails away from cultivated fields using deterrents, and to "pull" them onto artificial estivation supports where they do not cause damage. Results showed that red artificial supports are the most attractive to snails under laboratory and field conditions and that garlic extracts were powerful snail deterrents. These results offer a proof of concept for a push pull strategy against invasive snails and open new promising perspectives for snail management.

Technical Abstract: Four invasive Mediterranean snails (Theba pisana (Müller), Cernuella virgata (da Costa), Cochlicella acuta (Müller) and Cochlicella barbara (Linnaeus)) cost $170 million yearly to the grain industry in Australia. Their impact is mainly due to their estivation behavior: snails climb on cereal stalks to rest during summer, which coincides with harvest, causing grain contamination issues. Diverse management methods have been developed to regulate snail populations, with limited success. Our study aims at investigating the potential for a push pull strategy to divert invasive snails from cultivated fields. First, artificial estivation supports of different colors were tested under laboratory and field conditions and showed that red supports were the most attractive for these snails. Second, different substances were tested as potential snail deterrents (garlic, coffee, coffee grounds, copper). Garlic extracts were the most powerful snail deterrent and were shown to effectively protect an estivation support and food source from snails under laboratory conditions. These results, which were highly consistent for the four species, illustrate the potential of a push-pull strategy against invasive snails in Australia. A “push” part based on the use of a chemical deterrent repelling snails from the cultivated field, and a “pull” part based on offering attractive estivation supports for snails to aggregate outside the cultivated field. It is the first attempt to develop a push-pull strategy based on manipulating the estivation behavior of a pest and to rely on both visual and chemical stimuli to achieve results.