Meeting Abstract

103.1  Sunday, Jan. 6  Handedness and predation success in the stone crab Menippe mercenaria-adina WHITENACK, LB*; HERBERT, GH; BERT, T; Allegheny College; Univ. of South Florida; Florida Fish and Wildlife Conservation Commission lwhitena@allegheny.edu

The stone crab Menippe mercenaria possesses dimorphic claws, typically with a large, molar-tooth bearing, right crusher claw for breaking shelled prey and a smaller, left pincer or cutter claw for holding and stabilizing prey . While the majority of M. mercenaria hatch this way, molting errors, limb autotomization, and removal of crushing claws by fisheries can lead to reversed handedness after a number of subsequent molts. A major food source for M. mercenaria is the gastropod Strombus alatus, which has a right-handed or clockwise coiling direction. To investigate whether and how fisheries-induced handedness changes in stone crabs mightinfluence feeding interactions with right-handed coiling gastropod prey, we assessed experimentally whether right versus left-handed M. mercenaria-adina hybrids differed in prey handling behaviors and predation success on S. alatus. Preliminary results indicate that left-handed crabs had similar feeding success than right-handed crabs as estimated by numbers of prey “kills,” but their attacks resulted in less damage to S. alatus shells and less access to prey tissues . Energy gain per successful attack may, therefore, be less in left-handed stone crabs relative to their right-handed counterparts. The prevalence of certain types of damage differed as well; right-handed crabs tended to damage the shell ornamentation and siphonal canal more often, while left-handed crabs clipped the spire more often.