Three essays on production models in multispecies fisheries

Current regulations directed towards pelagic longliners do not fully incorporate the economic linkages between targeted species. This dissertation describes empirical production models of the pelagic longline fleet that can be used to evaluate allocative and distributional economic effects to the industry of proposed changes in HMS regulations. Furthermore, the model has broad applicability to multispecies fisheries worldwide.; Recently, a trend toward using dual-based models to explain the harvest technology of multispecies fisheries has developed in the commercial fisheries literature. Many of these analyses have assumed that inputs are fixed at the trip level; thus, researchers have argued that firms participating in multiple fisheries behave as revenue maximizers. The second chapter describes an empirical model of a multispecies fishery that assumes decision-makers are cost minimizers at the trip level. Using duality theory, optimal input demands are estimated using a 1996 data set that includes landings and economic information for the U.S. Atlantic pelagic longline fleet.; The methodology in chapter three takes the dual analysis a step further by incorporating the stochastic nature of harvest levels into estimation of the cost function using methodology that has never been applied in commercial fisheries economics. Additionally, an expectation-maximization algorithm is employed to handle missing economic information problems.; The model in chapter four uses portfolio theory to predict optimal outputs for the multispecies Atlantic longline fleet. These predictions reflect the vessel operator's species targeting strategy and may be used as a precursor to spatial targeting decisions.