Economic Benefits of Dolphins in the United States Eastern Tropical Pacific Purse-Seine Tuna Industry

This paper provides a profit-maximizing modelwith vessel-level dolphin mortality limits forpurse seiners harvesting tunas in the easterntropical Pacific Ocean. The model analyticallyderives the shadow price (estimated economicvalue) for dolphin mortality, the fishing-fleetsize, and the annual tuna harvest as functionsof a few key fishing parameters. The model alsoprovides a statistical method to determine theaccuracy of all needed parameter estimates. Thepaper then applies the model to the year 1996and the period from 1985 to 1987. The shadowprice measures the economic value to the UStuna fleet of dolphins lost in the harvestingof tuna. This value is essential whenattempting to evaluate the economic benefitsand costs to society of any action designed toreduce the mortality of dolphins in theharvesting of tuna in the eastern tropicalPacific Ocean. Copyright Kluwer Academic Publishers 2004