20. Interactive effects of acidification and hypoxia and adaptive potential in red abalone (Haliotis rufescens)

Boles, S.E. (1, 2)*, Swezey, D. S. (1,3), Aquilino, K.M. (1), Catton, C. A. (4), Hill, T.M. (5), Gaylord, B. (7), Rogers-Bennett, L. (4,6), Sanford, E. (7), Whitehead, A. (2)

1 Bodega Marine Laboratory, University of California, Davis, 2099 Westside Road, Bodega Bay, CA, 94923, USA
2 Department of Environmental Toxicology, University of California, Davis, 1 Shields Ave, Davis, CA 95616, USA
3 The Cultured Abalone Farm, 9580 Dos Pueblos Canyon Road, Goleta, CA 93117, USA
4 California Department of Fish and Wildlife Marine Region, Bodega Marine Laboratory, 2099 Westside Road, Bodega Bay, CA, USA
5 Department of Geology and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA
6 Karen C. Drayer Wildlife Health Center and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA
7 Department of Evolution and Ecology and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA

Anthropogenic activities are changing multiple climate variables simultaneously, thereby presenting complex challenges to marine species. As increasing atmospheric CO2 acidifies the oceans, there may simultaneously be an increase in the frequency, intensity, and duration of hypoxic events worldwide. To avoid reduced fitness associated with rapidly changing conditions, marine organisms must either migrate, acclimate, or evolve. For evolution to rescue species, adaptive genetic variation must currently exist within the species geographic range. In this project, we seek to test whether historically divergent environments might have enriched populations for genetic variants that are prepared for future climate conditions. Coastal upwelling zones within the California Current System (CCS) naturally transport deep-ocean water that has low pH and low oxygen into nearshore habitats annually, such that populations of organisms inhabiting these regions of the coastline may be pre-adapted to future ocean conditions. We are developing red abalone (Haliotis rufescens) as a comparative physiological, developmental, and evolutionary model system for studying the combined impacts of ocean acidification (OA) and hypoxia. We are comparing populations that occupy habitats within upwelling regions of the CCS (and experience annual OA and hypoxia) to those that live outside of the upwelling region of the CCS (and do not experience annual OA and hypoxia). We are exposing multiple families of developing larvae to combined acidification and hypoxia to test for differences in survival, morphology, and molecular signalling pathways between populations, and to identify genetic variants that are favoured in future environments. Knowledge of population and genetic variation relevant to future environments will provide a valuable resource for conservation managers. Our discoveries will be shared with aquaculture facilities, who are partners in this research program and involved in a larger collaborative effort to maintain business sustainability and innovation during an era of rapid climate change.