2/3 of all Pacific cod is landed in Alaska; most of that is trawl-caught. The quality of this fish can vary substantially depending on how well it was handled at sea. The highest quality is produced by freezer longliners, which process fish on board a short time after bringing it aboard.Factory trawlers can produce a high-quality product as well, if tows are short and fish is processed promptly. Most Alaskan trawlers delivering to shore-based processing plants hold their fish in refrigerated seawater tanks. Since the fish is not bled, its meat is normally not as white.
Pacific cod have a relatively short life of less than 20 years. They grow quickly, up to over 6 feet in length (although cod of this size are rare). Females are able to reproduce when they’re 4 to 5 years old (between 1.6 and 1.9 feet in length). Depending on their location, Pacific cod spawn from January through May on the shelf edge and upper slope in water 330 to 820 feet deep. They’re typically fertile; in fact, female cod can produce over 1 million eggs. After eggs are fertilized, they sink to the bottom and larvae begin to hatch within a month.
Pacific cod school together and move seasonally from deep outer and upper shelf areas where they spawn to shallow middle-upper shelf feeding grounds. They feed on clams, worms, crabs, shrimp, and juvenile fish. Halibut, sharks, seabirds, and marine mammals prey on Pacific cod. Pacific cod is also a major part of the diet of Steller sea lions.
Pacific cod are also known as grey cod because of their coloring – they’re brown or grayish with dark spots or patterns on the sides and a paler belly. They have a long chin barbell (a whisker-like organ near the mouth, like on a catfish) and dusky fins with white edges.
Pacific cod are found in the coastal North Pacific Ocean, from the Bering Sea to Southern California in the east and to the Sea of Japan in the west. Pacific cod are less common south of Northern California and are rare in Southern California. Pacific cod live on the shelf edge and upper slope in waters 300 to over 800 feet deep during the winter and move to shallower waters (less than 300 feet deep) in the summer. Larvae and small juveniles are found throughout the water column; large juveniles and adults live near the ocean floor and prefer habitats of mud, sand, and clay.
Science & Management
In Alaska, scientists and managers determine the population status of Pacific cod based on estimates of “spawning biomass,” a measure of the number of females in the population that are able to reproduce. Estimated biomass has fluctuated over the past few decades – the stock increased rapidly, peaked in the 1980s, then declined slightly and stabilized. Both Alaska stocks are near their target population levels, and biomass is projected to increase further in the next few years. The West Coast population of Pacific cod has never been formally assessed. Pacific cod are rarely available in this area in large numbers.
Changes in climate may be affecting the abundance of Pacific cod. Scientists at NOAA’s Alaska Fisheries Science Center and Oregon State University are working together to determine how climate change could impact growth and development of young Pacific cod in the Bering Sea. They will examine how temperature differences influence the timing and size of plankton blooms in the Bering Sea, which help determine the quality of habitat for Pacific cod.
The North Pacific Fishery Management Council develops regulations for the Alaska Pacific cod fisheries; the Pacific Fishery Management Council develops regulations for the fisheries off Washington and Oregon. NOAA Fisheries is responsible for approving and implementing these regulations.
In Alaska waters, Pacific cod fisheries are managed separately, but similarly, in the Bering Sea and Aleutian Islands and in the Gulf of Alaska. Fishermen must have a permit to participate in these fisheries, and the number of available permits is limited to control the amount of fishing. Every year, managers determine how much Pacific cod can be caught and then allocate this catch quota among groups of fishermen. Catch is monitored through record keeping, reporting requirements, and observer monitoring.
Pacific cod are rarely available in large numbers to be caught in the groundfish fishery off the West Coast. Managers use recent historical harvest numbers to set precautionary limits on annual catch for this population. The West Coast groundfish trawl fishery is now managed under a trawl rationalization catch share program.
Pacific cod is fished off the West Coast of the U.S. as well as in Canada, Alaska, Russia, and Japan. It grows quickly and can produce several hundred thousand eggs per year, making it resilient to fishing pressure, although it does form dense spawning aggregations that make large catches more likely. Overall inherent vulnerability is a moderate concern, according to Seafood Watch.
Pacific cod abundance has fluctuated, but the most recent stock assessments for the Bering Sea and the Gulf of Alaska showed that it was not overfished and overfishing was not occurring. The West Coast stock has never been formally assessed because the numbers are rarely big enough, according to the U.S. National Marine Fisheries Service. Seafood Watch reports from 2014 for Pacific cod noted a lack of independent Pacific cod stock assessments for Japan, and uncertainty about whether surveys and stock assessments conducted in Russia are scientifically independent.
Habitat impacts ( Wild)
The majority of Pacific cod in the U.S. and Canada is caught along with other groundfish using trawlers and bottom longlines. Trawling can do moderate damage to ocean habitats, particularly deep-water corals and sea whips. Seafood Watch noted that the U.S. and Canadian Pacific cod fisheries have spatial restrictions limiting the use of bottom trawl gear in order to mitigate the impact. Pot and jig gear are also used to a lesser extent, and they have minimal impacts. In Japan, Pacific cod are caught with gear that includes Danish seines and bottom trawls. While data on the habitat impact is sparse, Seafood Watch reported in 2014 that fishing moratoriums offer protection for deep-sea habitats there. Pacific cod in Russia are caught using bottom trawl, longline, gillnet, and seine gear. A 2014 Seafood Watch report noted concerns about the effects of trawling on sensitive substrate in the Russian fishery.
Bottom longlines in this fishery have accidentally caught endangered and threatened seabirds, but measures that include the Seabird Bycatch Reduction Program in Alaska and bycatch monitoring through the West Coast Groundfish Trawl Catch Share Program are having an impact, according to the U.S. National Marine Fisheries Service. Bycatch is also reduced with the use of pots, although they make up a small percentage of the gear used.
Bycatch data in the Japanese Pacific cod fishery is poor and not collected by a regulatory agency or research organization, according to a 2014 Seafood Watch report. Lack of data in the Russian Pacific cod fishery, along with concerns about marine mammal bycatch, led Seafood Watch to give the fishery a critical rating in 2014 for that criterion.
The U.S. West Coast cod fishery falls under the non-hake groundfish fishery, which has management that is considered strong according to a 2014 Seafood Watch report. The report also cites measures that include biomass reference points, harvest control rules, and catch limits. Management in the Alaskan Pacific cod fishery is considered to be highly effective and includes catch limits, observer counts, closures, and permits.
Seafood Watch considers the Canadian Pacific cod fishery management moderately effective. Despite some strong points, a 2014 report noted challenges with management strategy, implementation, and recovery of stocks of concern in the British Columbia groundfish fishery.
The Fisheries Agency of the Ministry of Agriculture, Forestry and Fisheries manages Pacific cod in Japan. Although bottom trawling and Danish seining are banned in coastal areas, Seafood Watch noted a general lack of management and expressed high concern about bycatch in a 2014 report.
In Russia, the Federal Fisheries Agency oversees the Pacific cod fishery. Management measures include setting total allowable catch levels, collecting scientific data, and restricting gear. While there has been documentation of illegal fishing, Seafood Watch noted that several changes to the law improved Russia’s enforcement capabilities. Data unavailability in general continues to be a concern, according to Seafood Watch.