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Management Procedures. Why has implementation been so slow?

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posted on 25.10.2021, 08:08 by Doug ButterworthDoug Butterworth
It is now some thirty years since the Management Procedure (MP) approach to fishery management was developed in the Scientific Committee of the International Whaling Commission. The reason this new approach was needed was that the previous “traditional” approach, consisting of a harvest control rule implemented using assessment-based estimates of resource status and productivity, had failed there. Reaching consensus on a catch limit using this approach had proved near impossible to achieve, first because of difficulties in agreeing a “best” assessment, and secondly because of the absence of an agreed procedure to take uncertainty in that assessment into account in some formal manner. The MP approach addressed these problems by requiring pre-agreement on the data inputs to use, together with an algorithm to calculate the catch limit which had been simulation tested and found (thanks to the role played by feedback) to exhibit reasonably robust performance across the range of the major uncertainties for the stock and fishery concerned. All fisheries face these same problems to some extent, so unsurprisingly it was not long before this MP approach was also applied in some other fisheries. However, despite the seeming advantages of the approach, growth in its application has been slow. The range of reasons for this are reviewed, and some suggestions are made on how these might best be addressed. Amongst the most important problems are the lack of a reasonably full understanding of the approach by many scientists, managers and other stakeholders. Allied to this has been failure to implement two key “guillotines” that are essential to ensure that a much lengthier process than required for the traditional approach to develop catch limit advice does not drag on yet longer. The first guillotine relates to fixing the data to be used in the process before detailed analysis commences. The second is the deadline by which to finalise the models to be used to represent alternative plausible resource and fishery dynamics so that uncertainties are properly considered, and not to allow subsequent changes, before the final simulation testing process commences.



Department of Mathematics and Applied Mathematics, University of Cape Town