Large marine ecosystems: analysis and management

Abstract

This contribution articulates a series of research issues concerning the definition, study and management of Large Marine Ecosystems (LMEs) and of the fisheries resources therein. The 57 biochemical provinces of Longhurst (1995, Progress in Oceanography 36) are suggested as standard for all global stratification of the world's oceans, because these "Longhurst areas", contrary to traditionally defined LMEs, permit direct comparisons of results from different disciplines. Examples of such comparisons, emphasizing the competition between fisheries and marine mammals, are given for the Pacific Ocean. The case is made that methods exist for rigorous descriptions of the trophic fluxes prevailing in such ecosystems, and based thereon, for dynamic modelling of at least the first-order impact of fisheries on LMEs. Also, emphasis is given on the need to reconstruct the earlier, unexploited states of ecosystems so as to obtain baselines for correctly evaluating fisheries impacts, and to evaluate the benefits foregone by present exploitation patterns. The need for fisheries scientists to reconceive their work from one principally devoted to optimizing short- and medium-term returns to the fishing industry to one serving a broader set of clients is emphasized. A recent initiative, the Marine Stewardship Council, serves as an example of the many new approaches that will be required if the public at large is to become an active stakeholder in conserving the biodiversity of LMEs.