Strategic management decision-making in a complex world: quantifying, understanding, and using trade-offs

The use of management strategy evaluation (MSE) techniques to inform strategic decision-making is now standard in fisheries management. The technical aspects of MSE, including how to design operating models that represent the managed system and how to simulate future use of management strategies, are well understood and can be readily applied, especially for single-species fisheries. However, MSE evaluations seldom identify strategies that will satisfy all the objectives of decision-makers simultaneously, i.e. each strategy will achieve a different trade-off among the objectives. This study illustrates the basis for identifying management objectives and representing them mathematically using performance measures, aswell as how trade-offs among management objectives have been displayed to various audiences who provide input into decision-making. Approaches and experiences are illustrated using case studies. Examples highlight the wide variety of objectives that can be considered using MSE, but that traditional single-species considerations continue to dominate the information provided to decision-makers. The desirability and consequences of having minimum acceptable standards of performance for management strategies, as well as difficulties assigning plausibility ranks to alternative states of nature, are found to be among the major challenges to effective provision of strategic advice on trade-offs among management strategies.