Effects of ocean acidification on behavior, development, and nutritional value of newly recruited coastal Dungeness crab (2018-20)

Aaron Galloway
Oregon Institute of Marine Biology
University of Oregon

Co-PIs: Julie Schram, (Oregon Institute of Marine Biology, University of Oregon); Email

Dungeness crab (Metacarcinus magister) is a commercially and recreationally important fishery for Oregon and other U.S. Pacific coastal states. However, the effects of ocean acidification (OA) on this species are largely unknown, which complicates fishery management. Dungeness crab early life stages (e.g., juvenile crabs) may be most vulnerable to changes in ocean acidity because of their high growth and molting rates. In recent management strategies, juvenile Dungeness crab recruitment has served as a good estimate for adult crab commercial catch, but this relationship could lose its predictive power if newly settled juvenile crabs are particularly susceptible to OA.

The research team will investigate sublethal OA effects on young Dungeness crab in a series of laboratory experiments. This work will quantify indirect (body condition) and direct (growth, shell formation, molt rates, survival, escape and feeding behavior) responses to current and future OA levels on the Pacific coast. As a comparative study to laboratory experiments, the researchers will partner with Oregon crab fishermen to capture adult crabs along the southern Oregon coast and evaluate their diets and body condition. In addition, the project will assess juvenile crab vulnerability to predation by older Dungeness crabs (i.e., cannibalism) and the effects of OA on the crabs’ ability to find potential food sources, including common baits used by fishermen.

Project results will improve predictions of lethal and sublethal effects on Dungeness crab due to ocean acidification and inform the management strategy of using juvenile crabs to estimate adult crab catches. This information is important to crab fishery managers, fishermen, and consumers. The research team will engage these key stakeholders through various mechanisms, including community presentations and a three-week artist-in-residence internship with the research team and the Charleston Marine Life Center.

OSG Thematic Areas:  Adaptation to acute and chronic coastal hazards; Human and natural dimensions of coastal and marine fisheries

National Sea Grant Office Plan Focus Areas: Healthy coastal ecosystems, Sustainable fisheries and aquaculture

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