Ocean acidification is causing increased predation on Mytilus californianus by specialist and generalist crabs

• Main Author: Toner, Miranda M.
• Other Authors: Corliss, Katherine M., Britsch, Melissa, Integrative Biology
• Format: Report
• Language: English
• Published: Oregon State University
• Subjects: Crabs; Ocean acidification; California mussel
• Online Access: https://ir.library.oregonstate.edu/concern/defaults/q237hx629

Ocean acidification is negatively impacting organisms that use calcium carbonate to form their shells. Increasing OA conditions are putting a strain on these calcareous animals by weakening their shells, thus causing them to become more vulnerable to predation. Worsening shell integrity may lead to a decline in hard-shelled prey populations as predators are able to break them open with greater ease. For this study, possible consequences of ocean acidification on predator-prey interactions was tested by comparing the number of normal to thin-shelled mussels eaten by two species of crabs. The time it took each crab to break into both types of mussel was also recorded. It was hypothesized that these crabs would eat a higher proportion of thin-shelled mussels over normal mussels due to their easier accessibility. It was found that crabs preferred thin-shelled mussels over normal mussels, and thus consumed them in higher quantities. Timed trials conducted on the shell-breaking times for each crab showed that thin-shelled mussels took significantly less time to open than normal mussels. These results provide insight into shifting future community structures as a direct product of ocean acidification.