Effect of environmental history on the physiology and acute stress response of the eastern oyster Crassostrea virginica

Abstract

Environmental history (regimes of water quality to which an organism has been exposed in the past) may influence how the physiology of eastern oysters Crassostrea virginica responds to future environmental conditions caused by climate change. Previous research has examined environmental history in a 1-dimensional framework, failing to capture environmental history complexity through space and time. In this study, we examined environmental history as a multi-faceted parameter, incorporating abiotic water quality components, such as temperature, pH, and salinity, that differ among locations. We also assessed how different lengths of environmental histories, defined as proximal and distal, affected oyster physiology and stress response. Finally, we compared the relative influence of abiotic components of environmental history on oyster physiology. We found that physiology and stress response are differentially affected by proximal and distal environmental history, demonstrating the importance of examining environmental history as a multi-faceted and dynamic parameter. Specifically, distal environmental history primarily influenced condition index and total antioxidant potential, while proximal environmental history primarily influenced glycogen content. Salinity of distal environmental history significantly shaped condition index, establishing salinity as a principal factor when considering acclimatization to variable environments. No water quality components were significant influences on glycogen and total antioxidant potential, providing opportunities for research on other components of environmental history. Identifying the temporal portion of oysters' environmental history that influences physiology supports future efforts to predict population tolerance to climate change. Additionally, examining multiple abiotic and biotic components of environmental history can elucidate means of acclimatization to future environmental change.