Collaborative research enhances selectivity in a lake fishery

Size and species selectivity are crucial for developing sustainable fisheries. Our objective was to estimate the selectivity of whitefish fisheries in a large European lake through a collaboration of fishers, regional managers, and scientists. Fishers were given special permits to test, within a common framework and together with scientists, selectivity enhancement strategies adapted to their own experiences. Fishers and scientists jointly tested gillnets and pontoon traps and how fishing depth, soak time, fishing season, and mesh size were affected by bycatches of undersized fish of sensitive species. Results indicated that the selectivity of the fishery could be increased, particularly by targeting whitefish adjacent to spawning sites where spatiotemporal overlap with bycatch species was lower. Proposed changes to the fishery, such as new gear, would be costly initially but could become profitable over time due to a lower cost of handling bycatch. Our findings demonstrated that co‐constructed knowledge can contribute to the governance of aquatic resources.