Shell Selection of the Hermit Crab, Pagurus longicarpus Say (Crustacea: Decapoda: Paguroidea), in Response to Acid-Treated Shells: A Laboratory Study

Abstract

Because of increased human-generated carbon emissions, ocean acidification is beginning to dissolve structures built by calcification, including the shells that all species of hermit crab (Crustacea: Decapoda: Paguroidea) use for protection. Since hermit crabs have been known to non-randomly select shells that best fit, this study explores whether the Atlantic long-clawed hermit crab, Pagurus longicarpus Say, 1817 preferentially chooses sturdier, intact shells when provided a choice between untreated shells (control) and acid-treated shells. Under controlled conditions (i.e., removal of stress from predator presence/effluent and intraspecific competition), not-surprisingly, most P. longicarpus preferred non-acid treated (control) shells by the end of testing period (1 hour) over heavily acid-treated shells; there was no statistical difference between the control shells and lightly acid-treated shells.