Paving a path for the shellfish industry to adapt to ocean acidification

Our primary objective is to evaluate the vulnerability and adaptation pathways of shellfish dependent stakeholders in the Pacific Northwest (PNW) to the hazard of ocean acidification (OA). We are developing an interactive, web-based geovisualization tool to map shellfish stakeholders’: 1) current and future exposure to OA, 2) socio-economic and cultural sensitivity to OA from dependence on four shellfish species with varied sensitivity to OA, and 3) adaptive capacity to prepare for or avoid harmful consequences of OA. We define exposure as the magnitude and frequency of undersaturated, high pCO2, low pH water - OA “hotspots” - coinciding with shellfish growing areas. To visualize where and when OA hotspots occur, our map includes an interactive time-slider for users to view monthly carbonate chemistry projections from a published model output of the California Current through 2050. Our map adds meaning to these model outputs by allowing users to filter the data view by locations where carbonate chemistry exceeds a selected shellfish species’ growth response threshold at larval or juvenile/adult stages. Growth responses to OA at different life stages were determined from previously published data on four commercially important species (C. gigas, O. lurida, M. californianus, and M. galloprovincialis). By representing physical projections relative to biological thresholds, our geovisualization tool enables OA exposure analyses that can identify the number of months an area’s chemistry exceeds a species’ threshold (magnitude) and how often in a given period (frequency). Ongoing and future work on the geovisualization tool includes mapping PNW sensitivity and adaptive capacity, as well as incorporating a bioeconomic model that identifies potential adaptation pathways and the costs associated with different management scenarios under intensifying OA conditions. Our map aims to assist shellfish stakeholders in making long-term management decisions most conducive to their local degree of vulnerability and adaptive capacity