MEPS 582:133-146 (2017)  -  DOI: https://doi.org/10.3354/meps12329

ABSTRACT: Stone crabs of the genus Menippe are harvested in a claw-only fishery along the Gulf of Mexico and southeastern Atlantic US coasts. As climate change continues to warm these areas, crabs are forced to cope with higher water temperatures. Altered environmental conditions may influence crab energetics by influencing both energy intake and expenditure. To prepare for a potential range expansion of the crabs, we investigated the energetic intake and expenditure of individual stone crabs. Crabs were found to respire 80 and 69% more following the loss of major and minor claws, respectively. Q₁₀, the factor by which the mass-specific respiration rates change as temperature is increased by 10°C, was 1.54. Mass-specific consumption of oysters in field cages increased by 15.8% for every 10°C increase in water temperature. Ingestion efficiency did not significantly vary with crab size, water temperature, or claw loss. We hypothesize that the ingestion efficiency of soft tissue did not change with the loss of the claws due to the unique feeding behavior of stone crabs. The front 4 walking legs were used more in food manipulation than both major and minor claws. Although current regulations were designed to promote sustainability and allow for the possibility of previously harvested crabs to reenter the commercially available stock, our results suggest that stone crabs may struggle to cope with fishery-style claw loss in warming conditions that are expected with continued climate change, especially in areas that are O₂-depleted.

KEY WORDS: Respiration · Ingestion efficiency · Temperature · Autotomization · Sustainability