Evaluating applications of shore-based camera monitoring to improve estimates of effort, retention, and compliance of recreational salmon fisheries

Abstract

In addition to being primary targets of recreational fisheries, Pacific salmon provide key ecosystem value in British Columbia, Canada. While data on commercial fisheries are historically well-researched, less is known about recreational fisheries and associated mortality. The purpose of this work is to demonstrate how autonomous shore-based cameras can integrate into, and improve upon, existing creel survey methods while providing new information related to recreational salmon fishery dynamics. Imagery from three locations in Sooke, British Columbia were used to estimate effort and retention by integrating creel survey data, and to improve understanding of compliance to a seasonal area-based fishery closure through two separate empirical studies. The approach here utilizes high-capture rates, allowing for robust temporal resolution, while integrating efficient data processing methods through a novel two-step image annotation process that was developed for the analysis of over 1.5 million images. The results from various temporal analyses suggest that cameras can substantially aid in improving the understanding of daily fishing patterns, while also providing validation for the optimal timing of existing creel surveys. Noncompliant fishing during a seasonal spatial closure was also notable and provides the first known study of salmon fishery compliance using cameras in British Columbia. Lastly, evidence was provided supporting substantial off-season fishing effort, which had previously been lacking in the existing monitoring framework. The subsequent recommendations from this work reveal that this monitoring approach could provide immediate and tangible benefits for improving recreational salmon fishing monitoring in British Columbia. Beyond, the approach that was developed can be applied at broader scales and could benefit managers with tools that can support camera monitoring of recreational fisheries to foster a greater understanding of stressors that impact vulnerable and at-risk fish species.