Assessing Local Adaptation and the Response to Ocean Acidification in Rock Scallops to Inform Aquaculture Practice

• Main Authors: Lowell, Natalie, Jackson, Molly, Vadopalas, Brent, Crim, Ryan, Davis, Joth, Hauser, Lorenz, Blake, Brady
• Format: Text
• Language: English
• Published: Western CEDAR 2016
• Subjects: Marine Biology; Natural Resources and Conservation; Pacific; Ocean acidification; Alaska
• Online Access: https://cedar.wwu.edu/ssec/2016ssec/climate_change_ocean_acidification/13

The shellfish aquaculture industry is among the first economic sectors to be negatively affected by ocean acidification, in part because changes in water chemistry interfere with shell formation and reduce survival and productivity. Populations already adapted to low pH may represent important genetic resources for the development of resistant strains. The protection of such genetic resources is of crucial importance in a rapidly changing environment, adding to traditional concerns of genetic interactions between wild and captive populations. The purple-hinged rock scallop (Crassadoma gigantea), a species native to the U.S. Pacific coast, is currently under consideration for commercial aquaculture. Across their range, rock scallops may exhibit population structure due to restricted gene flow and local adaptation that should be conserved. We will use whole genome scans of wild scallops to measure the degree of population structure and local adaptation at two spatial scales: among wild populations in California, Washington, and Alaska, and among wild populations within Washington. We will quantify neutral genetic divergence, explore molecular evidence for adaptive genetic differentiation, and identify discriminatory markers for routine screening of wild populations and captive broodstock. In addition, we will use a common garden experiment with an elevated pCO2 treatment to directly compare performance of larval families from California, Washington, and Alaska. Our findings will inform resource managers and aquaculture practitioners, and contribute to wild stock resilience and the sustainability of C. gigantea aquaculture.