Surface longline - Seabird interactions & accidental capture
Issue
Birds are attracted to surface longlines by baits near the surface and by discarded bait and offal from fishing vessels. Some birds dive down to eat the bait from hooks; some get hooked and drown. Surface longlining is also associated with relatively high catches of pelagic sharks as bycatch, including blue shark, porbeagle shark and mako shark.
Risk
Evidence of bird captures from overseas and in New Zealand's surface longline fleet suggests this may be a significant risk to seabird populations, some of which are considered threatened or endangered.
Extent of the issue
New Zealand has significant surface longline fisheries. However, apart from the Japanese joint-venture tuna fishery (where there is good observer coverage), we have relatively poor information on seabird deaths in these fisheries.
Trends
The Japanese jont-venture tuna fleet has done a good job of seabird mitigation in recent years. However, we know less about the performance of the domestic surface longline fleet.
Current management
Government has regulations that mean bird-scaring devices must be used by all vessels to keep birds away from baited hooks when the line is being set. As well as this, all longline vessels must either meet minimum line weighting requirement or else fish at night - which makes it harder for birds to see the baits.
Future management
Fishing-related risks for all New Zealand seabird species will be assessed as part of New Zealand's National Plan of Action (NPoA) to reduce seabird capture in fisheries. Treatment plans will be developed where risks are considered above 'acceptable' levels.
Documents / links
Documents around NPOA seabirds / seabird standard, Abraham & Thompson 2008
