Ocean biogeochemical models as management tools: A case study for Atlantic wolffish and declining oxygen

Abstract

Society is moving towards a no-analogue climate that will fundamentally affect ocean ecosystems and the socio-economic activities that depend on them. Warming has led to displacements of various populations, calling for an adaptation of fisheries management plans and Species at Risk recovery strategies. Dissolved oxygen (DO) has declined, but its impacts on habitat are muchless studied. Severe hypoxia is lethal, but even sublethal hypoxia can trigger species displacements. We use Atlantic wolffish (Anarhichas lupus) as a case study to investigate the impact of DO on optimal habitat on the Scotian Shelf, Canada, considering that their habitat becomes suboptimal atDOlower than ~ 65% saturation. First, we demonstrate thatDO has decreased using two observational climatologies before and after 1980, and that the spatial pattern of the associated expansion of low oxygen waters (DO