How good are alternative indicators for spawning-stockbiomass (SSB) and fishing mortality (F)?

Survey-based abundance indices (catch per unit effort, cpue) and harvest ratios (HRs) are usable proxies for spawning-stock biomass and fishing mortality (F). Here, we present an easy approach to calculate secondary indicators based on a public dataset. However, the performance of different cpue/HR indicator metrics varied between stocks, and, therefore, the adequate metrics for secondary indicators should be chosen for each stock after careful analysis by experts.