Understanding CO2 effects on Dungeness crab: population variability, temperature interactions, calcification process, and carbonate sensitivity
Why we care
Dungeness crabs support the most valuable fishery on the U.S. West Coast. Previous research shows lower survival and slower development in Dungeness crab zoea (young larval stage) when reared in high carbon dioxide conditions. This project helps us understand why, where, and under what conditions these effects occur. Answers to these questions will allow better projections of how Dungeness crab will fare in an acidifying ocean and provide critical data for projections of impacts on related species.
What we are doing
This project investigates regional variation in Dungeness crab to acidification, expanding the geographic range of previous studies to British Columbia. We will evaluate the relative impacts of acidification and climate-driven temperature change in multi-stressor experiments. This project aims to determine which of the carbonate chemistry parameters (pH, saturation state, partial pressure of carbon dioxide, dissolved inorganic carbon, and alkalinity) drive changes in Dungeness crab survival. This indicates which physiological processes are involved in responding to ocean acidification and those we expect to drive any field observations of biological changes from ocean acidification. Lastly, we use stable calcium isotopes as labels to help understand the calcification process throughout the Dungeness crab molting cycle. We can then assess this as a potential cause of observed mortality and the utility of using exoskeleton condition as a field indicator of acidification.
Benefits of our work
The research will explicitly evaluate potential mechanisms involved in observed field correlations between Dungeness crab larval exoskeleton morphology and ocean carbonate chemistry. These observations allow an assessment of Dungeness crab as a biological indicator of ocean acidification in the region.