• Projects
  • Reproductive Life History Analysis of Sablefish Populations off the Washington and California Coasts


Northwest Fisheries Science Center (NWFSC) Environmental and Fisheries Sciences EFS - Environmental Physiology; EFS - Marine Fish and Shellfish Biology


Sablefish Reproduction
Reproductive Life History Analysis of Sablefish Populations off the Washington and California Coasts
Sablefish (Anoplopoma fimbria) have a wide distribution along the Pacific coast, extending from Baja California to Alaska, the Bering Sea and through to the eastern coast of Japan. A unique feature of these fish is the wide variation in temperature and depth that sablefish experience throughout their life cycle, extending from depths 200m as adults to the surface as larvae and juveniles. While the landed weight of sablefish in the commercial fishery is relatively small, the exceptionally high value of this species ranks it 3rd in economic value to walleye pollock and Pacific cod. As such, sablefish are highly managed throughout the Pacific, and understanding the biology of this species is essential for proper management. The aim of this project is to characterize the reproductive life history of two populations of sablefish in coastal Washington and California.

Fish will be collected from the same geographical location on a monthly basis for one year. The reproductive status will be determined from gonadal histology and plasma sex steroid levels, and age will be determined from otoliths. It is expected that data on size, age, rate of gonadal development, seasonal timing of spawning, fecundity, frequency of reproduction, and potential shifts in distribution of sexes will be obtained. This study applies directly to the Magnuson-Stevens Fishery Conservation and Management Reauthorization Act, because the data will be used to improve stock assessments and estimates of spawning biomass in this commercially important species. This project is a cooperation with the commercial fishing industry and scientists at the Northwest Fisheries Science Center (NWFSC) and Southwest Fisheries Science Center (SWFSC).

Research Themes

Recovery and rebuilding of marine and coastal species
The Pacific Northwest is home to several iconic endangered species, including Pacific salmon and killer whales, and several rockfish species. Mandates such as the Endangered Species Act, MagnusonStevens Act, and the Marine Mammal Protection Act, grant NOAA Fisheries the authority to manage the recovery of depleted species and stocks. The NWFSC contributes to species recovery through research, monitoring and analysis, providing NOAA managers and regional stakeholders the tools and information they need to craft effective regulations and develop sustainable plans for recovery.

Research Foci

Characterize the population biology of species, and develop and improve methods for predicting the status of populations
To evaluate species status and recovery, it is necessary to understand key aspects of the population biology of the species in question. This includes basic information on abundance, age structure, recruitment, spatial distribution, life history and how the species interacts with its ecosystem. For some recovering species, including most overfished groundfish stocks, many ESA-listed Pacific salmon stocks, and high profile species such as Southern Resident killer whales, this basic information is often reasonably well understood. For other recovering species, such as Pacific eulachon and some ESA-listed rockfish species, even basic information (e.g. stock abundance) is unknown. Even for well-studied species, key information on survival rates for critical life stages and how the environment affects these vital rates is lacking. Without basic information on species dynamics, achieving other goals such as quantifying relationships between human activities and species recovery or even knowing if species recovery goals are being met will not be successful. The NWFSC, in partnership with regional stakeholders, including states, tribes and industry, is conducting research to collect and monitor critical demographic information for recovering species.


reproductive biology
field focusing on reproductive development, such as development of the gonads and gametes, and the process of reproduction
common name for Anoplopoma fimbria. Other common names include black cod and butterfish.


None associated


Class Actinopterygii
ray-finned fishes
Family Anoplopomatidae
Genus Anoplopoma
Order Scorpaeniformes
Phylum Chordata
Species Anoplopoma fimbria


Cortney Jensen
Jon Dickey
Jose Guzman
Mollie Middleton
Penny Swanson
Rick Goetz
Principal Investigator