Context dependence of the olfactory perceptual range in the generalist land snail Cornu aspersum

Abstract

Dispersal success in animals depends in part on their perceptual range, i.e., the distance from which they can acquire information about their environment. We studied how the olfactory perceptual range of a generalist species, the brown garden snail (Cornu aspersum (Müller, 1774)), varied under controlled conditions depending on the context in which stimuli were presented, whether alone or in the presence of another stimulus with opposite properties. Cornu aspersum preferentially orient themselves towards small nettle (Urtica dioica L.) patches, a highly palatable plant, and move away from repulsive plants if these stimuli are placed up to between 20 and 40 cm away from their starting point. A blend of palatable and repulsive plants, tested together, do not significantly influence the orientation of individuals in either direction. Cornu aspersum are thus capable of detecting and evaluating relatively small potential resource patches from a distance, enabling them to limit costly explorations, but this ability is context-dependent. These data could lead to a better understanding of the behaviour of C. aspersum in very heterogeneous landscapes in relation to this species’ ability to colonise a wide range of anthropised and fragmented habitats.