Management of Nothern Atlantic Bluefin Tuna An Application of the Shapley Value

In this paper a game theoretic setting is applied to the management of North Atlantic Bluefin tuna fisheries. The aim is to explore possible solutions for multilateral management by a regional conservation organization in accordance with the UN Convention on Straddling Fish Stocks and Highly Migratory Fish Stocks. The analysis is based on simulation results from a multi-gear age structured bioeconomic model developed for the North Atlantic Bluefin tuna fisheries, both for the East and for the West Stock. A characteristic function game approach (c-game) is used to analyse cooperative aggreements. The analysis is focused on the sharing of the total net returns from the fishery. In particular, Shapley values are calculated assuming three players for the East Stock: EU (European Union), OCS (Other Coastal States) and DWFN (Distant Water Fishing Nations) and three players for the West Stock: USA (United States), CAN (Canada) and DWFN (Distant Water Fishing Nations). Moreover, the cooperative solution as well as coalition solutions assume that the possible strategies are fixed strategies (either constant level of effort or constant level of catch). The simulation results show, as expected, that significant gains can be attained from cooperation. A distribution of the gains according to the Shapley values, could guarantee cooperation in many situations. However, this case study points out some particular cases where this solution is not enough to guarantee cooperation namely, from all coastal states.N/