Climate Change and the Future Productivity and Distribution of Crab in the Bering Sea
Crab populations in the eastern Bering Sea support some of the most valuable fisheries in the US, but their future productivity and distribution are uncertain given projected climate change. We explore observed and projected future changes in the productivity and distribution for the three largest stocks in the Bering Sea: snow crab, Tanner crab, and Bristol Bay red king crab.
Our results suggest the productivity of snow crab is related to the Arctic Oscillation and to ice cover; Tanner crab’s productivity and distribution are related to cod biomass and sea surface temperature. Aspects of red king crab distribution and productivity appear to be related to bottom temperature, ice cover, the Arctic Oscillation, and/or cod biomass. Projecting these relationships forward with available climate projection forecasts change of population of crabs depending area, which influences fishery productivity.
We link historical indices of environmental variation and important predator biomass with observed time series of centroids of abundance and extent of crab stock distribution; we also fit stock-recruit curves including environmental indices for each stock. We then use these identified relationships with projections from global climate models to forecast potential productivity and distribution scenarios for each stock.