The Dispersal of Cernuella-Virgata (Mollusca, Helicidae)

Abstract

The dispersal of the land snail Cernuella virgata was measured in South Australia by mark-release- recapture. Dispersal was not influenced by the paint used for marking, displacement of the snails during the marking process or crowding at release points. Snails moved out of a well-grazed permanent pasture to adjacent weedy roadside vegetation in early summer. They returned to the pasture in autumn. Factors which might direct this movement are discussed. Average movements varied between 0.1 and 0.4 m day-'. Some snails moved more than 25 m in one month in spring-summer and 50 m in 3 months in autumn-winter.