An effective harvest strategy using improved catch-curves

This paper describes and tests a harvest strategy for fish stocks where only annual catch weight, annual age frequencies of the catch, and knowledge of basic biological parameters are available. The method used to estimate current fishing mortality (FCUR) is based on a form of catch-curve analysis that accounts for selectivity. A harvest control rule that incorporates limit and target fishing mortality levels is used to calculate the following year's intended fishing mortality based on the estimate of FCUR. This is then used to adjust a reference catch to calculate the following year's recommended catch. The performance of this new harvest strategy in relation to defined management objectives is tested by management strategy evaluation for two example species with different life-history characteristics. The simulation results show that a harvest strategy using equilibrium assessment methods such as catch-curves can perform reasonably well when used in combination with an appropriate catch averaging period, and a suitable harvest control rule.