Groundfish Population Ecology Research on the West Coast

We assess the status and trends of groundfish stocks, research the ecological processes that influence their population dynamics, and continually refine our methodologies to improve stock assessment accuracy.

Yelloweye Rockfish

Sustainable management of the Pacific coast’s bountiful groundfish resources requires sound scientific guidance. We assess groundfish populations and provide estimates of the amounts of fish that fishermen can sustainably harvest. This information helps resource managers achieve a long-term balance between conservation and the economic benefits that fishery harvest provides to Pacific coastal regions.

Our Research

Conducting Stock Assessments

We work closely with the Pacific Fishery Management Council to evaluate and identify species for upcoming stock assessments (in even-numbered years) and interpret scientific findings to support their decision-making. We then provide the results of peer-reviewed stock assessments (in odd-numbered years) for use in management. We also collaborate with Canadian scientists to assess Pacific hake every year.

Aging Fish

Information on the age of fish helps us understand important aspects of their lives, including their growth, maturation, and the variability of reproductive success. We determine their ages by counting annual rings laid down in fishes’ ear bones, or otoliths. Our Cooperative Ageing Project, funded through a grant with the Pacific States Marine Fisheries Commission, is the primary source of new age data for Pacific coast groundfish.  

Understanding Linkages

We look for connections between environmental conditions such as ocean temperature, a stock’s geographic distribution, and aspects of its productivity, such as growth or recruitment success. Understanding these relationships between the fish and their ecosystem can reduce statistical uncertainties in the assessment and improve our short-term forecasts. 

Evaluating Management Strategies

We work with fishermen, fisheries managers, and other interested parties to create models that simulate potential management strategies, a process known as Management Strategy Evaluation. Management Strategy Evaluation is a tool that leverages information about the environment and groundfish stocks to understand the long-term risks of alternative harvest policies. Through an interactive process with stakeholders, Management Strategy Evaluation can help identify superior management approaches.

What’s Next

We expect to improve our ability to understand and model:

  1. Sub-populations of species along the coast, which may exhibit differences in growth or other processes.
  2. Impacts of environmental variability on reproductive success, growth, and natural mortality. 

We will also be evaluating the role that data from advanced technologies can play in future assessments. This work includes both at-sea collection of data–such as acoustic data collected with Saildrones–and analysis of otoliths with near-infrared spectroscopy, as part of a national initiative to expedite fish age determination.

Contacts

Population Ecology Program Contacts

Last updated by Northwest Fisheries Science Center on August 13, 2020