Evaluating bycatch avoidance in the US Atlantic Sea Scallop fishery

Abstract Objective The effectiveness of bycatch avoidance programs relies on changes in fishing behavior in response to spatiotemporal information on bycatch patterns. A voluntary bycatch avoidance program in the U.S. sea scallop Placopecten magellanicus fishery designed to prevent triggering bycatch allocation of Yellowtail Flounder Limanda ferruginea was implemented and maintained concurrently with other management measures. Detecting bycatch avoidance behavior and relative effectiveness for bycatch mitigation presents an analytical challenge. Methods We evaluated effectiveness of the bycatch avoidance program over the course of 4 years based on fishing behavior relative to bycatch advisories. Using loglinear models to compare frequencies, we examined the relationship between bycatch reports from participating vessels and bycatch advisories throughout the year in each of the 4 years. We compared results from self‐reported catch to data from a mandatory observer program for participating and nonparticipating vessels in the bycatch avoidance program. Result Significant associations between bycatch advisories and fishing locations indicated bycatch avoidance behavior, while accounting for the effect of sea scallop density on fishing location decisions. Evidence of avoidance behavior was stronger in earlier years of the program and varied spatially. Decreasing avoidance behavior coincided with revised bycatch management measures, which appear to have altered the incentives for bycatch avoidance. Conclusion We found differences in the fishing behavior of fishing captains who participated in the bycatch avoidance program when Yellowtail Flounder bycatch was perceived to threaten economic yield due to fishery closures. Bycatch mitigation program evaluations should consider the program objectives as well as incentives (and disincentives) in interpreting behavior.