Possible anti-predation properties of the egg masses of the marine gastropods Dialula sandiegensis, Doris montereyensis and Haminoea virescens (Mollusca, Gastropoda)

Abstract

Many marine mollucs deposit their eggs on the substrate encapsulated in distinctive masses, thereby leaving the egg case and embryos vulnerable to possible predators and pathogens. Although it is apparent that many marine gastropods possess chemical anti-predation mechanisms as an adult, it is not known from many species whether or not these compounds are widespread in the egg masses. This study aims to expand our knowledge of egg mass predation examining the feeding behavior of three species of crab when offered egg mass material from three gastropods local to the San Juan Islands. The study includes the dorid nudibranchs Diaulula sandiegensis and Doris montereyensis and the cephalospidean Haminoea virescens. The results illustrate a clear rejection of the egg masses by all three of the crab species tested, suggesting anti-predation mechanisms in the egg masses for all three species of gastropod.