In contrast to plants, predation on animals is usually lethal. Analysis of the effect of predation on animal populations and on predator-prey dynamics typically assumes this is the case. However, sublethal predation occurs in echinoderms, primarily on the arms of crinoids, asteroids, and ophiuroids. Sublethal predation is important in these echinoderms as it meets one of Harris' (1989) major criteria, affecting basic biological processes such as acquisition of food and allocation of nutrients to growth and reproduction. Sublethal predation would have an effect on their ecological role. It is essential to consider sublethal predation in the analysis of the life-histories of these species.