ISTS: Translating experimental results into fleet operations: Lessons in mitigating the bycatch of sea turtles, seabirds, and marine mammals

Crowder, L.B., T. Cox, R. Lewison, B. Wallace, R. Zydelis, W.J. Nichols, C. Safina, and A. Read. 2006. Translating experimental results into fleet operations: Lessons in mitigating the bycatch of sea turtles, seabirds, and marine mammals. Submitted paper, 26th Annual Symposium on Sea Turtle Biology and Conservation, Island of Crete, Greece, April 2006.

Fishermen and resource managers have made substantial progress mitigating bycatch (incidental take) of sea turtles, seabirds, and marine mammals through various methods, including physical modifications to fishing gear. Many bycatch mitigation measures have been developed and tested successfully in controlled experiments. The results of these tightly controlled experiments have led to regulations that require important changes to several fisheries, including: TEDs to reduce bycatch of turtles in trawls; streamers and dyed bait to reduce seabird bycatch in longlines; and acoustic pingers to warn marine mammals of the presence of gill nets. But even with rigorous testing, success in by-catch experiments may not lead to effective mitigation in commercial fisheries, especially when experimental conditions are relaxed in real-world conditions. Bycatch mitigation methods may be less effective when implemented by a fishery because of a lack of compliance, misuse of the gear modification, regional differences in fishing practices, or other factors. Such an efficacy 'discount' between experimental results and fleet implementation may have serious implications for management and conservation of species taken as bycatch. Here we consider the difference between experimental and implemented bycatch reduction and suggest approaches that may be necessary to increase the efficacy of bycatch reduction in industrial fisheries.