Gordon (1953, J. Fish. Res. Bd Can.
10, 442~457) used economic theory to predict how catch rates, price and fishing costs should balance in a multi-area, open-access fishery. We use the data from the Tasmanian rock lobster fishery to test this theory. We find that, as predicted by theory, areas with higher monetary and non-monetary costs have consistently higher catch rates than areas with lower costs. We show that this theory also predicts that an increase in price would result in an overall increase in catch rate, and suggest that in fisheries with spatial variation in costs, catch rates may be determined as much by economic factors as biological ones.
Introduction. Gordon (1953) considered the relationship between rates of return and costs in fisheries that take place in two or more areas. He used simple economic theory to show that if individual fishermen have the freedom to move between areas, have information on the relative catch rates to be obtained in different areas, and are attempting to maximize economic profit, the average rate of return (catch x price-costs) should be equalized in all areas. Using a simple three-area model, with costs proportional to distance from port, he showed that the catch rates should increase with distance from home port.
Hilborn and Ledbetter (1979) examined the spatial pattern in catch per week from the British Columbia (B.C.) salmon purse seine fishery and showed that catch rates were consistently different between areas of British Columbia. In one area of B.C. the total catch had increased greatly during their study and, as predicted by Gordon's theory, fishermen moved into this area to reduce the catch per vessel to its traditional level relative to other areas. Hilborn and Ledbetter believed that costs were roughly the same between areas and ascribed the observed discrepancies in catch rate between areas to nonmonetary costs such as distance from home. Hilborn (1985) examined the role of individual variation and suggested that