Trade policy and ecology

Trade sanctions on product exports are often used as measures for conservation of stocks of living resources. Two opposing approaches are investigated. The harvest approach argues that sanctions reduce the harvest, and thus protects the stock. It is shown that this does not consider the long run effects nor the effects of sanctions on the management system. The investment approach argues that increased price protects the stock, making the species a profitable investment. It is shown that this approach does not consider the asset effects of price changes, and that the sanctions usually increase the stock in an one species analysis. If the wildlife competes for land the conclusions may be different, but still sanctions usually works. If the manager has a joint management of several species, the stock effects of sanctions are ambiguous, depending on both the species interaction, and the profitability of the harvesting from each of them. In this case it is not possible to use intuitive reasoning, sanctions give distortions to all stocks simultaneously. The threat of extinction depends crucially on the unit cost in harvesting of depleted stocks. The paper concludes that trade policy is a too general measure for the management of living resources, and may implicate important economic distortions to the ecological system. Copyright Kluwer Academic Publishers 1996