Biologia Marina Papers!

ICES Journal of Marine Science Advance Access published May 3, 2007
Page 1 of 8

Tips and tricks in designing management procedures
´ ´ Rebecca A. Rademeyer, Eva E. Plaganyi, and Doug S. Butterworth
´ ´ Rademeyer, R. A., Plaganyi, E. E., and Butterworth, D. S. 2007. Tips and tricks in designing management procedures – ICES Journal of Marine Science, 64.

Management procedures (MPs) arebecoming widely used in fisheries management, but guidelines to assist in their construction, evaluation, and implementation are few. We provide simple guidelines by drawing on experience from developing and applying MPs in southern Africa and internationally. Suggestions are provided on how to choose between candidate MPs and on key trade-offs in selecting between data-based (empirical) andmodel-based formulations. Assistance is also provided in dealing with different sources of uncertainty, such as deciding which operating models should be included in a reference set used for primary simulation testing and tuning (in contrast to robustness or sensitivity tests), and on how weights for the associated alternative hypotheses are most practically assigned. Finally, some guidelines are given forpresenting the results effectively, which is one of the key challenges of a successful implementation process.
Keywords: management procedure, operating model, robustness, simulation testing, uncertainty. Received 30 June 2006; accepted 22 January 2007. ´ ´ R. A. Rademeyer, E. E. Plaganyi and D. S. Butterworth: MARAM (Marine Resource Assessment and Management Group), Department of Mathematicsand Applied Mathematics, University of Cape Town, Rondebosch 7701, South Africa. Correspondence to R. A. Rademeyer: tel: þ27 21 650 3656; fax: þ27 21 686 0477; e-mail: rebecca.rademeyer@uct.ac.za

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Introduction
Management procedures (MPs) (Butterworth and Punt, 1999) and similar frameworks such as management strategyevaluation (MSE) (Smith et al., 1999) are becoming more widely used in fishery management because they provide formalizations of longterm, robust strategies that are designed to satisfy multiple conflicting objectives. There are few guidelines available, however, to assist in their construction, evaluation, implementation, and presentation. We provide practical guidelines for new developers by ´ drawingon experience in southern Africa (Plaganyi et al., 2007) and internationally. MPs involve assessing the consequences of alternative options for management actions for both the target resource(s) and associated fisheries. Simulation trials ensure that the associated decision rules lead to performance that is robust to uncertainties about the dynamics of the resource being managed. The simulationframework essentially consists of an operating model (OM) to simulate the “true” system of resource dynamics and fishery and generate future resource-monitoring data typical of what would become available in practice, an estimator that provides information on resource status and productivity from these data, and a harvest control rule (HCR) that outputs a management action in the form of a totalallowable catch (TAC) or allowable fishing effort (Kell et al., 2006). Key steps in designing MPs are described, with suggestions for selecting the best option at each step. Given that the evolution of the MP approach has been accompanied by the introduction of several technical terms with specific meanings in an MP context, a glossary is provided in the Appendix to assist readers.

Constructing OMsThe first step in assessing the consequences of different management options is to model several possible scenarios for the underlying true dynamics for the resource population(s) of interest and the impact of exploitation. These OMs are used as the basis to compute how the resource responds to different future levels of catch or effort. Typical population dynamics models include age structure,...