Predator prey interaction between predatory gastropod Thais clavigera, barnacle Amphibalanus amphitrite amphitrite and mussel Brachidontes variabilis under ocean acidification

Since responses to ocean acidification (OA) are species-specific, it is impossible to extrapolate responses at the species level to community or ecosystem levels unless changes in species interactions under OA are known. We investigated predator-prey interactions between a predatory muricid gastropod Thais clavigera and its prey, the barnacle Balanus amphitrite amphitrite and mussel Brachidontes variabilis under three pCO₂ levels, 380, 950, and 1250 µatm. T. clavigera increased its searching time for B. amphitrite amphitrite at 1250 µatm pCO₂. At 950 and 1250 µatm pCO₂ levels, the prey consumption rate was dependent on the exposure time of T. clavigera and the longer the exposure, the lower was the prey consumption rate. The prey preference between B. variabilis and B. amphitrite amphitrite, however, was independent of pCO₂. The findings suggest that changes in predator-prey interactions under OA will result in long term changes of population dynamics of interacting species.