Effect of elevated CO2 on Dungeness crab (Cancer magister) larvae and juveniles: long-term survival, development rate, size and metabolic rate

Paul Mcelhany1, Shallin Busch2, Kelsey Donahue3, Amanda Lawerence4, Mike Maher3, Nicole Manteufel5, Danielle Perez1, Emma Reinhardt6, Kate Rovinski1 and Erin Tully6, (1)Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, Conservation Biology Division, Mukilteo, WA, United States, (2)Office of Oceanic and Atmospheric Research and Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, Ocean Acidification Program, Seattle, WA, United States, (3)NOAA Northwest Fisheries Science Center, Mukilteo, WA, United States, (4)University of Maryland Center for Environmental Science, Baltimore, MD, United States, (5)NOAA Northwest Fisheries Science Center, Conservation Biology, Mukilteo, WA, United States, (6)Office of Education, NOAA, Ernest F. Hollings Undergraduate Scholarship, Silver Spring, MD, United States
Abstract:
Previous studies have shown that Dungeness crab (Cancer magister) larvae are sensitive to elevated CO2, suggesting some risk from ocean acidification for this valuable species. We conducted long-term CO2 exposure experiments on zoea stage (>120d) and early juvenile stage (>300d) Dungeness crab by monitoring survival, development rate, size and base metabolic rate. These experiments confirm a decline in survival and slower development rate for zoea reared in elevated CO2. However, no effect on survival or development rate was observed for juvenile crabs. We did see small, but significant, effects on the size and base metabolic rate of juvenile crabs, which indicates that elevated CO2 imposed sub-lethal shifts in energy acquisition and/or allocation. We continue the challenging task of integrating these results into a comprehensive projection of future effects of ocean acidification on wild populations in a species with complex life history and wide geographic and environmental range.