Pacific Cod Research
Pacific cod (Gadus macrocephalus), also known as
grey cod, are moderately fast growing and relatively short-lived fish,
with a maximum age of approximately 18 years.Females reach 50% maturity at 4.4 years in the Gulf of Alaska and 4.9 years in the eastern Bering Sea (Stark, 2007). Total body length at 50% maturity was significantly smaller (503 mm) in the Gulf of Alaska than in the eastern Bering Sea (580 mm). Similarly, Pacific cod females grow significantly faster in the Bering Sea than in the Gulf of Alaska. Males reach a smaller maximum length in the Gulf of Alaska than females; in contrast, Bering Sea males reach a similar maximum length as females. Pacific cod are highly fecund and can produce up to 5.7 million ova each year.
Cod are demersal and
concentrate on the shelf edge and upper slope
(100-250 m) in the winter and move to
shallower waters (<100 m) in the summer. Cod prey on clams, worms, crabs, shrimp,
and juvenile fish. In turn, they are eaten by halibut and marine
mammals. Pacific cod are taken with trawl, longline, pot,
and jig gear. Cod begin to recruit to trawl fisheries at age 3, but are
not fully recruited to all gear types until about age 7.
Pacific cod are managed under two Fishery Management Plans: one for the Bering
Sea/Aleutian Islands region and the other for the Gulf of Alaska region.
The Fishery Management Plans control the fishery through permits and
limited entry, catch quotas, gear restrictions, closed waters, seasons, bycatch limits and rates, and other measures.
During 2015, pollock made up 67% of the total groundfish catch off Alaska. The pollock catch for 2015 was 1,490,780 metric tons (t), up approximately 3% from 2014.
The 2015 catch of flatfish, which includes yellowfin sole, rock sole and arrowtooth flounder, was 245,860 t or 11% of the total 2015 Alaska groundfish catch, down about 24% from 2014.
Pacific cod accounted for 321,100 t or 14.4% of the total 2015 Alaska groundfish catch. The Pacific cod catch was down about 4% from 2014.
Other important species (% of total 2015 catch and % change from 2014) are: Atka mackerel 54,500 t (2.4%, up 70%),
sablefish 11,690 t (.05%, down 5%), and rockfish 668,660 t (3%, up 6%).
- 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.
- FARLEY, E., R. A. HEINTZ, A. G. ANDREWS and T. P. HURST.
2016. Size, diet, and condition of age-0 Pacific cod (Gadus macrocephalus) during warm and cool climate states in the eastern Bering Sea. Deep-Sea Res. II. 134:247-254. http://dx.doi.org/10.1016/j.dsr2.2014.12.011
- WEINBERG, K. L., C. YEUNG, D. A. SOMERTON, G. G. THOMPSON, and P. H. RESSLER.
2016. Is the survey selectivity curve for Pacific cod (Gadus macrocephalus) dome-shaped? Direct evidence from trawl studies. Fish. Bull., U.S. 114:360-369. http://dx.doi.org/10.7755/FB.114.3.8
- SPIES, I., and A. E. PUNT.
2015. The utility of genetics in marine fisheries management: a simulation study based on Pacific cod off Alaska. Can. J. Fish. Aquat. Sci. 72:1415-1432. DOI: 10.1139/cjfas-2014-0050.
- KASTELLE, C. R., T. E. HELSER, J. McKAY, and D. M. ANDERL. 2015. Age Validation of Pacific Cod Using Stable Oxygen Isotope (δ¹⁸O) in Otoliths. AFSC Quarterly Report Feature (April-May-June 2015) 4 p. (.htm pages). Online.
- HURST, T. P., D. W. COOPER, J. T. DUFFY-ANDERSON, and E. V. FARLEY.
2015. Contrasting coastal and shelf nursery habitats of Pacific cod in the southeastern Bering Sea. ICES J. Mar. Sci. 72:515-527.
- Spatial and Temporal Variation in Otolith Elemental Chemistry of Young-of-Year Pacific Cod in the Gulf of Alaska
By: MARY ELIZABETH MATTA, JONATHAN SHORT, THOMAS HELSER, OLAV ORMSETH, JESSICA MILLER
Conference: Western Groundfish Conference (19th), Newport, OR, Feb 2016
(2016 poster, .pdf, 896 KB) Online.
- Patterns in Octopus Predation by Pacific Cod, Gadus macrocephalus, in the Eastern Bering Sea
By: SEAN K. ROHAN, TROY W. BUCKLEY
Conference: American Fisheries Society, 145th Annual Meeting, Portland, OR, Aug 2015
(2015 poster, .pdf, 1.27 MB) Online.
Age Validation of Pacific Cod Using Stable Oxygen Isotope (δ¹⁸O) in Otoliths
Use of Shelf, Slope, and Basin Habitat by Age-0 Walleye Pollock and Pacific Cod in the Gulf of Alaska
A 200-Year Archeozoological Record of Pacific Cod Life History as Revealed Through Ion Microprobe Oxygen Isotope Ratios in Otoliths
- Additional publications, posters, and reports.