Survey Design Optimization for Estimating the Exploitable Biomass of a Fishery Accounting for Non‐Sampling Errors

To manage a large commercial fishery it is necessary to have a good estimate of its exploitable biomass. Knowledge of this parameter is crucial since the fishery may be developed, preserved and managed by establishing catch limits and season length according to exploitable biomass. Great economic loss of opportunity and sudden decline in the stock may be consequences of management decisions based on poor estimates of the exploitable biomass. This paper presents methods for determining an optimal survey sampling strategy with the objective of estimating exploitable biomass. In particular, alternative sampling strategies are considered that account specifically for non‐sampling errors, e.g. incorrect aging, that occur in estimating the distribution of catch at age required for estimating exploitable biomass. Our results are important because they account for anticipated non‐sampling errors and utilize important biological notions about how the dynamics of the fishery affect exploitable biomass in specifying an optimal survey sampling strategy. A real application involving Pacific halibut is given to illustrate the methodology.