Fishery management of straddling stocks is conditional on available knowledge about relevant environmental shocks, such as El Nino events, affecting stock behavior. But knowledge of these issues is scant, particularly in developing world fisheries. Using per-trip, geo-referenced data for the period 1994-2004, we test the hypothesis that sea surface temperature anomalies related to El Nino events have systematically induced the Chilean fleet exploiting the Chilean (straddling) jack mackerel stock to fish beyond the 200-nm zone more frequently and farther south (than its traditional fishing grounds) than in the absence of El Nino. We take this as an indirect testing of El Nino-triggered effects on the spatial distribution of the Chilean straddling jack mackerel stock in the southeast Pacific. While measuring environmental variability, we also control for regulatory regime shifts, fleet technology features, and seasonal and price effects. Our estimation results clearly support the stated hypothesis.
