Tree climbing by the snail Cepaea nemoralis (L.): a possible method for regulating temperature and hydration

Three sheltering strategies employed by the snail Cepaea nemoralis are described: climbing objects, aestivating on the soil surface, and returning to underground refuges. The number of snails that climbed bushes was analysed by correlation regression. An equation incorporating maximum daily temperature, rainfall for the last 3 days, and the interaction of these factors explained 95% of the variation observed (P < 0.0001). Snails more than 1.8 m above the ground were significantly more dehydrated than those individuals found lower (P < 0.05). The distance climbed by snails, however, was not related to their size (P = 0.4112). The interrelationship of habitat structure, sheltering behavior, and microclimate is discussed in relation to selection of color morphs.