Evaluating and Advancing the Use of Shore‐Based Observers for Scientific Sampling and Catch Verification in High‐Volume Fisheries

ABSTRACT Shore‐based observers are increasingly being used in place of at‐sea observers to monitor and sample commercial fisheries catch. However, few evaluations assess whether these programs meet their stated goals or how to optimize them, and industry data are rarely tested for accuracy despite serving as the foundation for catch accounting. Using a high‐volume trawl fishery as a case study, we evaluated observer performance, assessed the accuracy of industry data, and present a transferrable framework for evaluating observer performance and optimizing sampling. Observers performed well under expanded duties, meeting high‐priority objectives, nearly meeting secondary goals, and detected species at low catch fractions (~0.7%). Comparisons with industry data revealed under‐reporting or aggregation for some managed species, underscoring the need for independent verification. Results highlight that shore‐based observers can fulfill expanded duties, maintain core functions, and provide critical checks on industry‐reported data. The framework employed here is applicable to other programs seeking to evaluate and optimize shore‐based monitoring programs.