Patterns of shell damage among snails from a coppice woodland in Sussex, England

Snail shells from a coppiced, ancient woodland were examined quantitatively for signs of damage. Six distinct patterns of damage were found. One type of damage was believed to be inflicted during predation by a snail Aegopinella nitidula, preferentially attacking its own species, another was believed to be caused by beetle predation. These two predators accounted for 42% of the damage observed and 17% of mortality. The relationships between type of damage, maturity of snail and time since coppicing are examined. Species preferences by the predators are also analysed and possible effects on the population. Only one species, Discus rotundatus, which has pronounced ribs on the shell, showed evidence of survival and shell repair and possible evolutionary implications are discussed.