Examination of effectiveness of seabird bycatch mitigation measures for small-scale longline vessels fishing north of 23ºN specified in CMM 2015-03

This paper shows results from on-board researches conducted in 2015 and 2016 in order to examine effectiveness of tori line for small-scale longline vessels fishing north of 23°N, agreed at WCPFC12. The effectiveness of tori lines of different materials for small-scale longline vessels was tested using a commercial small-scale longline vessel from February to March in the Western North Pacific off Japan. Experimental fishing operations demonstrated substantial reduction of frequency of seabird’s attacks on baited hook during line setting and number of seabirds bycaught compared to case of no tori line regardless of the difference in material of tori line. Trial implementation of a short streamer tori line on the small-scale longline vessel caused entanglement of fishing gear during line setting.