Predator deterrence of early developmental stages of temperate lecithotrophic asteroids and holothuroids

Lecithotrophic echinoderm eggs and larvae are likely to possess deterrents to predation because they are large, lack behavioral defenses, and are ofte n conspicuously colored. We performed laboratory feeding assays to test det errence in multiple developmental stages of common shallow-water lecithotro phic asteroids and holothuroids in the San Juan Islands, Washington (seven asteroids, five holothuroids) to five functionally diverse, potentially sym patric predators (sculpins, shrimp, ascidians, and two species of anemones) . At least one developmental stage of most echinoderm species tested deterr ed at least one predator (causing food rejection). Using sculpins as predat ors, the hypothesis that deterrence varied among developmental stages of a species was rejected for the four echinoderm species in which older embryos were tested. Different predator species often responded differently to the same developmental stage. Compared to the invertebrate predators, sculpins were usually the most sensitive assay predator. The present results provid e additional support for the hypothesis that lecithotrophic eggs and larvae are deterrent, and in this study the deterrents persisted through early li fe stages. Because these stages lack obvious structural or behavioral defen ses, the most likely source of their deterrence is chemical. (C) 2001 Elsev ier Science B.V. All rights reserved.