Translating ecosystem indicators into decision criteria

Abstract

Defining and attaining suitable management goals probably represent the most difficult part of ecosystem-based fisheries management. To achieve those goals we ultimately need to define ecosystem overfishing in a way that is analogous to the concept used in single-species management. Ecosystem-based control rules can then be formulated when various ecosystem indicators are evaluated with respect to fishing-induced changes. However, these multi-attribute control rules will be less straightforward than those applied typically in single-species management, and may represent a gradient rather than binary decision criteria. Some ecosystem-based decision criteria are suggested, based on indicators empirically derived from the Georges Bank, Gulf of Maine ecosystem. Further development in the translation of ecosystem indicators into decision criteria is one of the major areas for progress in fisheries science and management.