A Management Strategy for Sedentary Nearshore Species that Uses Marine Protected Areas as a Reference

Abstract

Classical approaches to fisheries stock assessment rely on methods that are not conducive to managing data‐poor stocks. Moreover, many nearshore rocky reef species exhibit spatial variation in harvest pressure and demographic rates, further limiting traditional stock assessment approaches. Novel management strategies to overcome data limitations and account for spatial variability are needed. With the ever‐increasing implementation of no‐take marine protected areas (MPAs), there is great potential for improving decision making in management through comparisons of fished populations with populations in MPAs at spatially explicit scales. We developed a management strategy that uses a combination of data‐based indicators sampled inside and outside of MPAs as well as model‐based reference points for data‐poor, sedentary nearshore species. We performed a management strategy evaluation of this MPA‐based decision tree model for a hypothetical population of grass rockfish Sebastes rastrelliger in California. We introduced process, observation, and model uncertainty in numerous scenarios and compared these scenarios with the precautionary approach currently used to manage data‐poor species. Our model consistently improved total catches while maintaining the biomass and spawning potential ratio at levels well within acceptable thresholds of management. We suggest further exploration of this MPA‐based management approach, and we outline a collaborative research program in the California Channel Islands that may well be suited for testing an experimental management procedure.