ENVIRONMENTAL VARIABILITY EFFECTS ON MARINE FISHERIES - 4 CASE-HISTORIES

The changing nature of marine fisheries requires management approaches that recognize and include ecosystem and environmental effects. There fore, we review some examples of exploited fishery stocks in which env ironmental control is a major contributor to structuring the abundance and distribution of the stock. Four examples, taken from studies of n orthern cod (Gadus morhua), cod and haddock (Melanogrammus aeglefinus) larvae, the eastern oyster (Crassostrea virginica), and Antarctic kri ll (Euphausia superba), are given that clearly illustrate environmenta l control on the fishery. From these examples, we argue that future ma nagement strategies for exploited fisheries must include effects of en vironmental variability. In particular, management strategies must be flexible enough to include delayed responses to environmental variatio ns that result from the transfer of perturbations from larger to small er scales and vice versa. This capability requires an understanding of where linkages between the physical environment and the species of in terest occur. Development of this knowledge requires input from a vari ety of disciplines, coordinated research programs, and considerable co operation at national and international levels.