Presenter: Robert Ahrens (NOAA Fisheries)

Description:
Globally, fisheries bycatch is a major threat to many long-lived marine species. Significant effort has gone into developing best practices for reducing bycatch-related mortality, not only to the benefit of the species of interest (birds, marine mammals, turtles, and sharks) but also to ensure the viability of fishing operations. Collaborating with the University of Florida, NOAA-PIFSC, NOAA-PIRO, the WPRFMC, as part of an ecosystem-based fisheries management initiative, developed the Protected Species Ensemble Random Forest (PSERF) model for the Hawai’i and American Samoa Longline Fisheries. The project goal was to understand static and dynamic physical features that relate to interactions with protected species. As with its counterparts, such as TurtleWatch and EcoCast, using PSERF to identify physical features associated with areas of high interaction rates allows for the development of tools to facilitate dynamic ocean management. A useful feature of the PSERF modeling approach is its ability to produce relationships for  species where interactions are rare events. This feature allows for the development of models across a range of species and provides insight into tradeoffs that may exist when fisheries respond to single species management strategies. To achieve this insight, PSERF model output must be coupled with models that describe the expected behavior of fishing fleets in response to management strategies so that the redistribution of effort and the potential impact of effort redistribution on target and bycatch species can be accounted for. We present the PSERF modeling result for a suite of protected species that interact with the Hawai’i longline fishery as well as preliminary results for potential areas of avoidance scenarios.