Design of operational management strategies for achieving fishery ecosystem objectives

Ecosystem objectives in fisheries management usually flow from high-level n ational policies or strategies and international agreements. Consequently t hey are often broadly stated and hence are difficult to incorporate directl y in management plans. Predicting the results of any management action is v ery uncertain because the dynamics of ecosystems are complex and poorly und erstood. Methods to design and evaluate operational management strategies h ave advanced considerably in the past decade. These management-strategy-eva luation (MSE) methods rely on simulation testing of the whole management pr ocess using performance measures derived from operational objectives. The M SE approach involves selecting (operational) management objectives, specify ing performance measures, specifying alternative management strategies, and evaluating these using simulation. The MSE framework emphasizes the identi fication and modelling of uncertainties, and propagates these through to th eir effects on the performance measures. The framework is outlined and illu strated by three ecosystem-related applications: management of benthic habi tats and broad fish community composition; by-catch of species of high cons ervation value; and food-chain interactions and dependencies. Challenges to be overcome before broader ecosystem-related objectives can he fully handl ed are discussed briefly. (C) 2000 International Council For the Exploratio n of the Sea.