Factors affecting protected species captures in domestic surface longline fisheries [+ summary & Recommendations to ACAP SBWG11]

Bycatch of protected species, such as seabirds, is a known issue in various fisheries including surface longlining (SLL). For SLL fisheries in New Zealand, mandatory bycatch mitigation measures include the use of hook-shielding devices (hookpods) and/or tori (streamer) lines, as well as night setting and line weighting. However, there exists a variety of gear configurations and environmental conditions that could further influence bycatch of protected species in SLL fisheries—variables that are often unavailable for analysis unless collected via experimental New Zealand trials. However, variables that could potentially influence non-protected species bycatch were recorded annually as part of New Zealand’s fisheries observer services. These additional data provided the opportunity to assess as yet unexplored risk factors that could influence the capture of protected species including seabirds, New Zealand fur seals, sharks and rays, dolphins and whales, and turtles by small SLL vessels and then to inform the development of potential mitigation strategies...con't

ACAP SBWG11 Doc 23 Summary & Recommendations:

ACAP currently recommends the use of branch line weighting, night setting, bird scaring lines, hook-shielding devices, underwater bait setting devices and time-area fishery closures. The recommendation is that the most effective way to reduce seabird bycatch in pelagic longline fisheries is to use the following three best practice measures simultaneously: branch line weighting, night setting and bird scaring lines.