Inferring a Biopolitical Consensus View of Stochastic Dynamics for Management of a Transboundary Fishery

Management of trans-boundary fisheries is a complicated problem with biological, legal, economic and political implications. We propose a simple stochastic differential-equation model to describe a biopolitical consensus view of fish stock dynamics. Estimates of the drift and diffusion terms of 3 stochastic differential equations are obtained using data from the southern bluefin tuna (SBT) fishery with a method based on the Kolmogorov-Smirnov statistic. We refer to these estimated equations as alternative biopolitical consensus views of SBT stock dynamics. Each of these is used to generate a time series of optimal harvest that achieves the objective of maximising the present value of expected fishery returns. These time series of optimal harvests are then compared to actual harvests for the period 1981-1997.