Testing mechanistic explanations of observed correlations between environmental factors and marine fisheries

Based on observed correlations, marine fisheries are often hypothesized to depend on environmental factors. Since correlations are unreliable as a pre dictive tool, it is desirable to seek mechanistic explanations for observed correlations. This paper considers methods available for testing such mech anistic explanations. As a specific example, we consider the optimal stabil ity window, proposed as a mechanistic explanation of observed correlations between the survival of North Pacific salmon stocks and the state of the at mosphere over the North Pacific in winter, as applied to the coastal waters and fisheries of southern British Columbia, Canada.