Purse Seine Guidebook
Minimize the Risk of Capture: During Fishing
Target Large Schools
Published science shows that fishers can reduce bycatch of non-tuna species simply by targeting larger schools of tuna. In the Canadian Journal of Fisheries and Aquatic Sciences, Dagorn et al. (2012) found that the total amount of bycatch is more dependent on the number of sets than on the total catch of tuna.
Fishers should target schools larger than 10 tons to reduce the total number of silky shark bycatch by 21% to 41%. Overall, using this method will cut the amount of total non-target bycatch by 23% to 43%, depending on the ocean region.
Tons of sharks captured per tons of tuna. Infographic: Dagorn et al. (2012)