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 2012, pollock made up 61.9% of the total groundfish catch off Alaska. The pollock catch for 2012 was 1,310,330 metric tons (t), up approximately 2% from 2011.
The 2012 catch of flatfish, which includes yellowfin sole, rock sole and arrowtooth flounder, was 321,530 t or 15.2% of the total 2012 Alaska groundfish catch, down about 2% from 2011.
Pacific cod accounted for 329,040 t or 15.5% of the total 2012 Alaska groundfish catch. The Pacific cod catch was up about 8% from a year earlier.
Other important species (% of total 2012 catch and % change from 2011) are: Atka mackerel 49,020 t (2.3%, down 8%),
sablefish 13,850 t (0.7%, up 7%), and rockfish 55,450 t (2.6%, up 8%).
- RAND, K. M., P. MUNRO, S. K. NEIDETCHER, and D. G. NICHOL.
2014. Observations of seasonal movement from a single tag release group of Pacific cod in the eastern Bering Sea. Mar. Coastal Fish. 6:287-296.
- NICHOL, D. G., S. KOTWICKI, and M. ZIMMERMANN.
2013. Diel vertical migration of adult Pacific cod Gadus macrocephalus in Alaska. J. Fish Biol. 83:170-189.
- MARSH, J. M., N. HILLGRUBER, and R. J. FOY.
2012. Temporal and ontogenetic variability in trophic role of four groundfish species -- walleye pollock, Pacific cod, arrowtooth flounder, and Pacific halibut -- around Kodiak Island in the Gulf of Alaska. Trans. Am. Fish. Soc. 141:468-486.
- SPIES, I.
2012. Landscape genetics reveals population subdivision in Bering Sea and Aleutian Islands Pacific cod. Trans. Am. Fish. Soc. 141:1557-1573.
- WEST, C. F., S. WISCHNIOWSKI, and C. JOHNSTON.
2012. Pacific cod (Gadus macrocephalus) as a paleothermometer: Otolith oxygen isotope reconstruction. J. Archaeol. Sci. 39:3277-3283.
- URBAN, D.
2012. Food habits of Pacific cod and walleye pollock in the northern Gulf of Alaska. Mar. Ecol. Prog. Ser. 469:215-222.
- A 200 Year Archeozoological Record of Pacific Cod Life History as Revealed Through Ion Microprobe Oxygen Isotope Ratios in Otoliths
By: THOMAS HELSER, CRAIG KASTELLE, JOHN VALLEY, ARON L. CROWELL, IAN ORLAND, REINHARD KOZDON, TAKAYUKI USHIKUBO
Conference: ICES Annual Science Conference, Coruna, Spain, Sept 2014
(2014 poster, .pdf, 1.4 MB) Online.
- Climate Change Impacts on Predator-prey Dynamics in the Bering Sea: Changes to Foraging Rate and Prey Demand of Walleye Pollock, Pacific Cod, and Arrowtooth Flounder
By: KIRSTIN K. HOLSMAN, KERIM AYDIN
Conference: Alaska Marine Science Symposium, Anchorage, AK, Jan 2014
(2014 poster, .pdf, 1.35 MB) Online.
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
Otolith Microchemical Fingerprinting: Assessing Juvenile Pacific Cod Habitat Utilization in the Gulf of Alaska
Preliminary Age Validation of Pacific Cod Using Stable Oxygen Isotope (d18O) Signatures in Otoliths
- Additional publications, posters, and reports.