An Age-Structured Bioeconomic Simulation of U.S. Silver Hake Fisheries

Abstract

Abstract We present a bioeconomic simulation of the U.S. fisheries for silver hake Merluccius bilinearis, an abundant species distributed over the northwest Atlantic continental shelf and historically important to both U.S. and foreign fishing fleets. The model combines elements of agestructured population and harvest yield models with a two-equation price response model. The analysis evaluates biological benefits of interest to managers, such as future yields or rebuilding of parental stock, as well as future revenues and net present value of interest to harvesters. In one set of simulations, yield and revenue response surfaces were generated for varying levels of fishing mortality (F) and selection at age under constant annual recruitment. In another, a stochastic stock–recruitment function permitted assessment of yield and revenue trajectories over time given variable annual recruitment. Under equilibrium conditions, response surfaces for both total fishery yield and revenue are asymptotic with increas...