Groundfish Assessment Program

Research

Photo of a basket of fish and invertebrates

The AFSC Groundfish Assessment Program (GAP), in addition to regularly conducting bottom trawl surveys, also investigates biological processes and interactions with the environment to estimate growth, mortality, and recruitment to improve the precision and accuracy of forecasting stock dynamics.
Impacts of bottom trawls on the seafloor and the description of bottom type are also being studied in the Bering Sea and Aleutian Islands.

*Featured Items*

Alaska Bathymetry, Sediments, and Smooth Sheets Go there >>

Validating and improving species distribution models for structure forming invertebrates using an independent survey in the eastern Bering Sea. Go there >>

Is the survey selectivity curve for Pacific cod (Gadus macrocephalus) dome-shaped? Direct evidence from trawl studies. Go there >>

Recent Poster Presentations, Publications, Reports & Activities

KASTELLE, C. R., T. E. HELSER, J. L. MCKAY, C. G. JOHNSTON, D. M. ANDERL, M. E. MATTA, and D. G. NICHOL. 2017. Age validation of Pacific cod (Gadus macrocephalus) using high-resolution stable oxygen isotope (δ18O) chronologies in otoliths. Fish. Res. 185:43-53. http://dx.doi.org/10.1016/j.fishres.2016.09.024 Online.
SOMERTON, D. A., R. A. McCONNAUGHEY, and S. S. INTELMANN. 2017. Evaluating the use of acoustic bottom typing to inform models of bottom trawl sampling efficiency. Fish. Res. 185:14-16. http://dx.doi.org/10.1016/j.fishres.2016.09.029 Online.
STEVENSON, D. E., and R. R. LAUTH. 2012. Latitudinal trends and temporal shifts in the catch composition of bottom trawls conducted on the eastern Bering Sea shelf. Deep-Sea Res. II 65–70:251-259. http://dx.doi.org/10.1016/j.dsr2.2012.02.021 Online.
GARDNER, J. R., J. W. ORR, D. E. STEVENSON, I. SPIES, and D. A. SOMERTON. 2016. Reproductive parasitism between distant phyla: Molecular identification of snailfish (Liparidae) egg masses in the gill cavities of king crabs (Lithodidae). Copeia 104:645-657. http://dx.doi.org/10.1643/CI-15-374 Online.
Using Triggered Cameras to Determine Fish Behavior in Rocky, Untrawlable Areas
By: KRESIMIR WILLIAMS, CHRIS ROOPER, MIKE LEVINE, ALEX De ROBERTIS
Conference: Western Groundfish Conference (19th), Newport, OR, Feb 2016
(2016 poster, .pdf, 468 KB) Online.
Introducing the Working Group on Maturity Assessment and Reproductive Variability of Life Stages
By: SUSANNE McDERMOTT, SANDI NEIDETCHER, CHRISTINA CONRATH, PAUL SPENCER
Conference: Western Groundfish Conference (19th), Newport, OR, Feb 2016
(2016 poster, .pdf, 1.85 MB) Online.

See the poster and publications databases for additional listings.

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