Quantitative estimates of contact with seafloor habitats by longline trap and hook fishing gear

Abstract Despite increasing calls for sustainability and ecosystem objectives to manage fishing gear interactions with benthic habitat there are few quantitative approaches for assessing risks from bottom fisheries. Risk assessments for bottom longline fisheries are particularly challenging due to a lack of information for estimating habitat contact from longline gear. In this paper, we demonstrate how data sensors and video cameras deployed on fishing gear can be used to quantify habitat–contact area for sensitive benthic taxa (corals, sponges, and sea whips) from bottom longline trap and hook gear used by the British Columbia Sablefish (Anoplopoma fimbria) fishery. Our habitat–contact estimates indicate that Sablefish fishing gear has had zero contact with sensitive benthic habitats in 91.8% of the area fished over the last 17 years. For habitats within 8.2% of Sablefish fishing areas that experience some contact from fishing gear, the majority are only contacted once. This indicates that most habitats contacted by Sablefish gear are expected to have a minimum of 17 years to recover between subsequent gear contact. We demonstrate an approach for estimating habitat–contact area from fishing gear that can be widely implemented across longline fisheries, addressing a key data gap in in bottom-impacts research. Our habitat–contact estimates provide essential information for risk assessments that can inform management decisions on the acceptable trade-offs between habitat preservation and fishery benefits over fine spatial scales.