The behavioural response of slugs and snails to novel molluscicides, irritants and repellents

The behavioural response of the slug Deroceras panormitanum (Lessona and Pollonera) and the snail Oxyloma pfeifferi (Rossm?ssler) to novel molluscicides was investigated in choice and no-choice experiments. Low-light video-recording in combination with automated tracking and event recording was used to identify the repellent and irritant effects of (1) cinnamamide, (2) copper ammonium carbonate, (3) a mulch, (4) a horticultural ground-cover matting impregnated with a copper formulation and (5) urea/formaldehyde. In the no-choice experiments the products had a stronger irritant effect on the snails than on the slugs. All products tested except the mulch significantly reduced the locomotor activity of both the slugs and snails. The most effective product, cinnamamide, reduced snail locomotor activity by 94% and track length by 96%. The overall repellent effect of the treatments in the choice experiments was stronger in the slugs; where presence, locomotor activity and track length in the treated area were significantly reduced by all products. The avoidance of treated areas exceeded 95% with the mulch (for slugs) and with copper ammonium carbonate (for snails).