A Game Theory Analysis of Management Strategies for the Southern Bluefin Tuna Fishery

Abstract

Management of the southern bluefin tuna population involves the identification of an overall policy which is not only biologically sound, but also economically viable to all participants. While there has been concern since the early 1980s about the state of the population of this species, it is only very recently that there has been widespread recognition that there is some danger of at least commercial extinction of the southern bluefin tuna. The population structure of the southern bluefin tuna fishery was simulated over a twelve year cycle, initiated at a 1970 age-class. Simulations were repeated under the impact of 81 hypothetical harvesting policies. These policies were constructed from the combination of nine Australian and nine Japanese harvesting strategies. The Australian strategies reflected harvesting policies centred in one or more of the major areas of the coastal operation (New South Wales, South Australia and Western Australia), while the far more general Japanese strategies identified low to high levels of harvest taken from catches of tuna with narrow to broad age distributions. For each of these harvesting policies, the payoff to Australia and Japan was evaluated and the parental biomass ascertained. This information provided economic and biological indicators of the state of the southern bluefin tuna fishery under the effect of particular joint harvesting policies.