Pelagic Longline Fleet Research Articles

Predicting Optimal Targeting Strategies in Multispecies Fisheries: A Portfolio Approach

When regulations are species specific but the species are part of a multispecies fishery, studies show that harvest rates are correlated such that net revenues attributed to each species are also correlated. This correlation suggests that portfolio theory is well suited for multispecies fisheries that exhibit joint productive characteristics. This paper uses a portfolio approach to model the behavior of fishermen faced with multiple targeting options in a randomharvest fishery. The approach draws from the expected utility hypothesis and financial portfolio theory to predict optimal targeting strategies. The methodology is applied to the pelagic longline fleet operating in the U.S. Atlantic Ocean, Caribbean, and Gulf of Mexico. The model provides evidence that area closures aimed at reducing juvenile swordfish mortality will be more effective in certain regions. Efficient risk-return frontiers are also generated for use in predicting targeting behavior in lieu of a closure.

A Bioeconomic Analysis of Management Alternatives for the U.S. North Atlantic Swordfish Fishery

A bioeconomic model of the North Atlantic swordfish (Xiphias gladius) fishery is developed to evaluate policy-relevant management options as changes from the status quo. The model accounts for heterogeneity in vessel and trip characteristics, including the number of sets placed and catch composition. Results indicate that five-year economic returns to the U.S. Atlantic pelagic longline (PLL) fleet can be increased by reducing juvenile swordfish mortality or fleet size (and possibly changing fleet composition). These policies may not be effective, however, if implemented simultaneously. Domestic management of the swordfish fishery was found to be effective, despite the small share of the international quota. Lastly, producer surpluses earned by the domestic PLL vessel owners are significantly affected by: (1) changes in swordfish demand (due to, for example, the recent chef's boycott), (2) success at negotiating the swordfish quota share, (3) catch rates, and (4) relative costs of heterogeneous vessels and trip behavior.