Autotomy in the Asian Shore Crab (Hemigrapsus Sanguineus) in a Non-Native Area of Its Range

Abstract

Abstract Numerous taxa have the ability to autotomize parts of their bodies to increase survivorship in dangerous or stressful situations. Effects of autotomy on a surviving individual's subsequent ecological function is not well understood for most species. In this study, we provide the first quantification of autotomy patterns within a population (frequency of injured individuals) and within an individual (frequency of missing pereopods, or limbs) of the Asian shore crab Hemigrapsus sanguineus. This crab, member of the family Grapsidae, is a recent introduction to the eastern coast of North America. Of 95 crabs sampled, 42% were missing at least one limb, with larger crabs missing more limbs than smaller crabs. Of the sample, 16% were missing at least one cheliped, with chelipeds more likely to be lost than walking limbs. These rates of limb loss are comparable to those of other crabs in their native ranges. Limb loss patterns affected feeding rate and size of prey consumed. Crabs missing one cheliped f...