The ecology of the Stock Island tree snail Orthalicus reses reses (Say)

Abstract

A study to determine the life history and behavior of the Stock Island Tree Snail, Orthalicus reses reses (Say) (Pulmonata: Bulimulidae), was conducted during May-August 1981 and August-October 1982 in the southern Florida Keys. A follow-up assessment of these populations was conducted in July 1986. The activity of the snail was found to be linked to rainfall patterns. Statistical analysis indicated that population size was not limited by species of tree available for colonization. The diet of the snail was determined by stomach content analysis and substrate examination and was found to consist of epiphytic growths on tree surfaces. Reproductive events were observed and growth rate and sources of mortality were examined. The density and composition of a population on Stock Island were determined. Human activity was determined to have a negative impact on the Stock Island populations. Comparative data for O. floridensis and Q. reses nesodryas were included where they were available.