Assessment

The FRAM Stock Assessment Team leads assessment activities for Pacific coast groundfish. Analysts conduct fishery stock assessments to estimate the current status and future trends in the abundance and productivity of west coast groundfish resources. The team also conducts rebuilding analyses, which examine the future status of overfished stocks and the probability of recovery under a variety of harvest strategies. The peer-reviewed assessment and rebuilding results provide the scientific basis for the management of the groundfish fisheries off the West Coast of the United States, including the setting of Overfishing Limits (OFLs) and Allowable Biological Catch (ABCs) as mandated by the Magnuson-Stevens Fishery Conservation and Management Act of 2007.

Most groundfish stock assessments and stock assessment review (STAR) panels are conducted on a biennial schedule (in odd-numbered years) to accommodate the Pacific Fishery Management Council’s (PFMC) management process. The exception to this is Pacific hake (also known as Pacific whiting), which is assessed and reviewed annually. Major assessments, known as benchmark assessments, are reviewed within the Council’s STAR process, which includes a multi-day review by a panel comprised of independent reviewers, a member of the Council’s Scientific and Statistical Committee (SSC), and representatives from the Council’s Groundfish Management Team (GMT), and Groundfish Advisory Panel (GAP). For some species, previously reviewed assessment models are updated with new observations from data sources already in use. Because the structure of these models has already been reviewed through the STAR process, the review of these updates is limited to the SSC, prior to use by the Council. More information regarding the current stock assessment and STAR panel schedule can be found on the Pacific Fishery Management Council’s website.

During “off-assessment” years, analysts conduct research on a wide variety of topics to improve the understanding of and ability to model West Coast groundfish populations. The Stock Assessment Team also works with FRAM’s Observer and Survey Teams, as well as with state fishery agencies, to ensure that efficient and effective objectives are established for the collection of the biological data that supports assessment activities. The collaborations continue with developing methods to streamline data extraction, processing and synthesis.

Current research projects by the Stock Assessment Team include:

• Developing methods to quantify and incorporate spatial and temporal variability in life history characteristics into stock assessment models.
• Exploring methods to incorporate climate-growth relationships into stock assessment models.
• Using bomb radiocarbon to validate otolith ages.
• Processing basic biological information (e.g. maturity and growth) for unassessed and data-limited stocks.
• Developing prior probability distributions for stock assessment parameters through meta-analytic and theoretical methods.
• Improving statistical analyses for fishery sampling and survey standardization.
• Testing stock assessment methods through simulations.
• Developing new tools for visualizing and diagnosing stock assessment model performance.
• Improving methods for visualizing spatial patterns in fisheries and ecosystem data, and conducting spatial analyses to enhance stock assessments or address other agency priorities, such as work on cold-water corals.
• Evaluating advanced sampling technologies (e.g., autonomous underwater vehicles, remotely-operated vehicles, camera-equipped trawl gear) for future use in measuring habitat-specific densities.
• Developing assessment approaches for data-limited stocks.
• Incorporating ecosystem considerations into stock assessment models.

Members of the Stock Assessment Team serve on a variety of Pacific Fishery Management Council advisory bodies, including the Scientific and Statistical Committee (SSC), Groundfish Management Team (GMT), and Ecosystem Plan Development Team. Team members are also active on national committees, such as the National Assessment Methods working group, the Fisheries and the Environment (FATE) steering committee, and the Allowable Biological Catch working group. They have also served as independent technical reviewers for stock assessments and fisheries analyses from around the world, as well as for domestic grant and fellowship programs and articles submitted to peer-reviewed scientific journals. FRAM scientists have provided training in both statistical programming and stock assessment methods for other NOAA facilities and other fisheries research organizations. The Stock Assessment Team has close ties to both the University of Washington and Oregon State University, with several members serving on graduate student committees, participating in joint workshops, and periodically presenting guest lectures.