NOAA Fisheries manages over 475 fish stocks in the United States, often supported by results from quantitative fishery stock assessment models. Historically, stock assessments have been conducted at broad, spatially aggregated scales based on panmictic, dynamic pool assumptions. However, recent guidance in NOAA Fisheries’ Next Generation Stock Assessment Improvement Plan has emphasized the need to develop and implement spatially explicit stock assessment models that better align with the complex population structure and spatial dynamics of marine species and associated fisheries. While spatial stock assessment models have been increasingly applied over the past two decades in a research context, they have only been sparingly implemented as operational models that serve as the basis of management advice. Building upon recent NOAA-funded research, including the Spatial Processes and Stock Assessment Methods (SPASAM) group, the Spatially Integrated Life Cycle (SILC) model, the Vector Autoregressive Spatio-Temporal (VAST) model, the Pacific Sablefish Transboundary Assessment Team (PSTAT), and the International Workshop on Spatial Stock Assessment Methods (Link), this project aims to improve tools for implementing operational spatial stock assessments that incorporate spatial dynamics of marine species. This effort will help streamline NOAA’s transition towards spatially explicit modeling approaches, and, thereby, increase opportunities to incorporate ecosystem- and climate-based linkages into assessments at multiple scales.
The Alaska Fisheries Science Center (AFSC) is seeking a postdoctoral associate to conduct research aimed at developing, applying, and simulation testing next-generation spatial stock assessments. In particular, the Marine Ecology and Stock Assessment (MESA) program is interested in exploring the implications of spatial structure in the assessment and management of sablefish (Anoplopoma fimbria) in Alaskan waters. Sablefish are a highly mobile, wide-ranging, deep-sea species that are a valuable resource to Alaskan fishermen. Although the AFSC has conducted a continuous mark-recapture program for sablefish for over 30 years, the spatial dynamics and potential implications of climate change and marine heatwaves on the sablefish resource are not well understood.
The successful applicant will explore the development and implementation of spatially explicit models for sablefish, and will work closely with researchers at the AFSC and NWFSC that develop operational stock assessment models. The project may include, but is not limited to: developing applied spatial models that integrate traditional Brownie tagging models and comparing that approach to the integration of a newly developed Diffusion-Advection-Taxis movement and tagging model (R package ATM); simulation comparisons of the robustness of spatially stratified and spatiotemporal modeling frameworks; development and implementation of spatially integrated life cycle models that incorporate multistage stock recruit relationships; and using fine-scale spatially explicit agent based simulators to test the robustness of spatially explicit and spatially aggregated assessment models. The applicant will have the opportunity to guide the project focus based on interests and skills, and a large repository of existing code and resources will be available from ongoing research efforts. Strong programming and quantitative skills along with a background in stock assessment modeling are prerequisites.
Stock Assessment; Spatial Modeling; Tag-integrated Models; Spatiotemporal Models; Sablefish; Integrated Life Cycle Models; Biologging; Animal Movement