Pacific Ocean Perch (Sebastes alutus)

• Pacific ocean perch populations are very healthy in Alaska and are rebuilding to sustainable levels off the West Coast of the United States.
• Strict management measures have allowed Pacific ocean perch stocks to rebuild in Alaska. A rebuilding plan was implemented for this species off the West Coast in 2003.
• Pacific ocean perch is low in saturated fat and very high in selenium, phosphorus, and vitamin B12. For more on nutrition, see Nutrition Facts. (USDA)
• Pacific ocean perch is a highly valued commercial fish in the northwest Pacific Ocean. Fifty-one million pounds of Pacific ocean perch were landed in 2006, at a value at $10.5 million.

Sustainability Status

Biomass: Off the West Coast, Pacific ocean perch biomass is 69% of the biomass needed to support maximum sustainable yield (B_MSY). Stocks in the Gulf of Alaska and BSAI are very healthy, with biomass at 16% and 32% above B_MSY, respectively.
Overfishing: No
Overfished: No
Fishing and habitat: In Alaska, bottom and pelagic trawls are used to catch Pacific ocean perch. In the Gulf of Alaska, bottom trawl fisheries are responsible for most of the bycatch of coral and sponges. Effects on non-living substrate are unknown, but the heavy-duty "rockhopper" trawl gear commonly used in the fishery is suspected to move around rocks and boulders on the bottom. In recent years, trawlers have begun to use pelagic trawl nets to target Pacific ocean perch by using hydroacoustics to locate schools and dip catch from it, with minimal bottom contact. There is currently no directed fishery for Pacific ocean perch off the West Coast and therefore no impact on habitat from fishing for this species.
Bycatch: In Alaska, the largest bycatch groups in the combined rockfish trawl fishery are Pacific cod, arrowtooth flounder, and sablefish. Off the West Coast, Pacific ocean perch are a rebuilding species. There are management measures in place to prevent a targeted fishery for the species, so no bycatch is associated with catches of Pacific ocean perch, as they are an incidentally caught species themselves.
Aquaculture: There is currently no commercial aquaculture of Pacific ocean perch in the U.S.

Science and Management

The Gulf of Alaska (GOA) fishery for Pacific ocean perch (POP) is regulated under the GOA Groundfish Fishery Management Plan. The plan controls the fishery through permits and limited entry, catch quotas (TACs), seasons, in-season adjustments, gear restrictions, closed waters, bycatch limits and rates, allocations, regulatory areas, record keeping and reporting requirements, and observer monitoring. In the BSAI, the fishery for POP is regulated under the BSAI Groundfish FMP with measures similar to those within the GOA FMP.

Off the West Coast, the POP fishery is managed by the Pacific Fishery Management Council (PFMC) as part of the Pacific Coast Groundfish FMP. Groundfish are managed through a number of measures including harvest guidelines, quotas, trip and landing limits, area restrictions, seasonal closures, and gear restrictions. All sectors of the groundfish fishery are constrained by the need to rebuild groundfish species that have been declared overfished. NMFS declared POP overfished in 1999, and the PFMC adopted a rebuilding plan for the stock in 2003. Catch of POP in the commercial and recreational fisheries is constrained by area closures and catch limits. Recreational catch of POP is also constrained by seasonal closures.

NMFS implemented the Groundfish Vessel Buyback Program in 2003 to reduce the number of vessels and permits fishing for groundfish off the West Coast to increase productivity of the fishery, help financially stabilize the fishery, and conserve and manage fish. In 2003, the Pacific Fishery Management Council also began using depth-based management for commercial and recreational groundfish fishing in order to avoid overharvest. Depth-based management means that some depth zones are closed to fishing. Because this can be difficult to enforce, managers are implementing vessel monitoring systems (VMS) to determine if a vessel is fishing in a closed area. Read more about VMS here, too. POP is currently no longer overfished or undergoing overfishing.

Life History and Habitat

Life history, including information on the habitat, growth, feeding, and reproduction of a species, is important because it affects how a fishery is managed.

• Geographic range: Off the coast of North America, Pacific ocean perch are found from southern California to the western boundary of the Aleutian Archipelago, but are most common from Oregon northward. They are also found from Honshu, Japan to Cape Navarin in the Bering Sea.
• Habitat: Pacific ocean perch is a slope rockfish, primarily living in deeper waters of the upper continental slope and along the edge of the continental shelf. They can be found from 82 to 2,700 feet deep. In the summer, adults inhabit shallower depths, especially those between 490 and 980 feet. In the fall, the fish apparently migrate farther offshore to depths from 980 to 1,400 feet. They reside in these deeper waters until about May, when they return to the shallower summer waters. Larvae and juveniles are pelagic; subadults and adults are benthopelagic (living and feeding near the bottom as well as in midwaters or near the surface). Adults are associated with both sandy and rocky benthic habitats, as well as benthic habitats that include structure-forming invertebrates, such as corals.
• Life span: Long - the maximum age in Alaskan waters has been estimated at 98 years.
• Food: Pacific ocean perch are carnivorous. Larvae eat small zooplankton (tiny floating animals). Juveniles feed on crustaceans. Adults eat shrimp and other crustaceans, squid, and small fishes. Pacific ocean perch often move off-bottom at night to feed, apparently following daily krill migrations.
• Growth rate: Slow.
• Maximum size: 20 inches and 4.4 pounds.
• Reaches reproductive maturity: Males mature at 4 to 13 years and females mature at 5 to 15 years, but mostly in 5 to 9 years for both.
• Reproduction: Females can have 10,000 to as many as 500,000 eggs. Eggs are fertilized internally.
• Spawning season: Eggs are fertilized from September to October off British Columbia and Washington. Larvae are released months after mating, primarily from January to April off Washington. A few fish release larvae in August and October as well.
• Spawning grounds: Among seamounts and other steep areas.
• Migrations: Pacific ocean perch winter and spawn in deeper water then move to feeding grounds in shallower water in the summer to allow gonads to ripen. Adults form large schools almost 100 feet wide, to 260 feet deep, and as much as 4,265 feet long. Juveniles form bell-shaped schools near the surface.
• Predators: Predators of Pacific ocean perch include sablefish and Pacific halibut. Other predators may include Pacific cod and arrowtooth flounder. Pelagic juveniles are eaten by salmon, and benthic juveniles are eaten by lingcod and other large demersal fish.
• Commercial or recreational interest: Commercial
• Distinguishing characteristics: Pacific ocean perch are light red, including their fins. They have dark, olive-green areas on their back under the soft dorsal fin and on the caudal peduncle (the narrow part of the body to which the tail attaches).

Role in the Ecosystem

Adult Pacific ocean perch feed primarily on euphausiids (krill). Euphausiids are also a major item in the diet of Alaska pollock. Recent declines in the biomass of Alaska pollock could lead to an increase in the availability of euphausiids, which would then have a positive impact on Pacific ocean perch abundance. Pacific ocean perch are preyed upon by a variety of other fish at all life stages, and to some extent marine mammals during late juvenile and adult stages.

Additional Information

Market name: Ocean Perch

Biomass

Biomass refers to the amount of Pacific ocean perch in the ocean. Scientists cannot collect and weigh every single fish to determine biomass, so they use models to estimate it instead. These biomass estimates can help determine if a stock is being fished too heavily or if it may be able to tolerate more fishing pressure. Managers can then make appropriate changes in the regulations of the fishery.

The West Coast stock of Pacific ocean perch was declared depleted by the Pacific Fishery Management Council (PFMC) in 1981. The PFMC discouraged targeting Pacific ocean perch while allowing continued fishing on other species, but the stock did not recover and the PFMC recommended more restrictive measures. In 1998, Pacific ocean perch biomass was estimated to be only 13% of the unfished level, leading NMFS to declare the stock overfished in 1999. The PFMC adopted a rebuilding plan for Pacific ocean perch in June 2003. The stock is no longer overfished and overfishing is not occurring.

Adult Pacific ocean perch were one of the most abundant stocks in Alaskan waters prior to large catches taken by foreign fleets in the 1960's; Pacific ocean perch biomass is once again becoming one of the largest in the North Pacific. A rebuilding plan was implemented in 1995 for the Gulf of Alaska stock, and the stock was rebuilt in 1997. Estimated total biomass (age 2 and greater fish) gradually increased from a low near 100,000 tons in 1980 to around 300,000 tons for 2005. In the BSAI, estimated survey biomass was 871,272 tons in 1960, declined to 106,736 tons in 1978, and increased to 577,724 tons in 2006. The total biomass has shown a similar trend as the survey biomass, with the 2006 total biomass estimated at 453,772 tons.

Note: Biomass estimates for Pacific ocean perch age 3 and older are shown in the graph for West Coast and BSAI stocks. Biomass estimates for Pacific ocean perch age 2 and older are shown for stocks in the GOA.

Landings

Landings refer to the amount of catch that is brought to land. Off the West Coast, historic Pacific ocean perch catches were high and were harvested primarily by foreign vessels prior to passing of the Magnuson Stevens Fishery Conservation and Management Act in 1977. Catches declined from 20,000 metric tons during the mid-1960s to less than 600 metric tons in 1999, when the stock was declared overfished. Pacific ocean perch is currently subject to rebuilding requirements, but some retention is allowed as incidental catch for targeted fisheries on other healthy stocks. Catch has been restricted by the PFMC since 1979 to promote the rebuilding of the resource. Landings were reduced below 900 metric tons by 1995; subsequent landings fell steadily until reaching between 60 and 150 metric tons per year from 2002 to 2006. There is currently no directed fishery for POP, but they are taken incidentally in both trawl and non-trawl fisheries off Washington, Oregon, and Northern California.

The U.S. fishery took over in the BSAI in 1990 and recorded the highest Pacific ocean perch removals since 1977. Catches in the BSAI have ranged from 12,000 to 20,000 metric tons per year since 1990. The domestic fishery began to grow in the GOA in 1985 and expanded each year until 1991 due to increasing annual quotas. From 1991 to 1995, overall catches diminished due to the enactment of more restrictive management policies, such as reducing the total allowable catch (TAC) to promote rebuilding of Pacific ocean perch stocks. Since 1996, catches of Pacific ocean perch have increased again, as good recruitment and increasing biomass for this species have resulted in larger TACs.

Note: U.S. commercial landings are shown for the West Coast in the graph. U.S. catch is shown for Alaska. Catch includes fish that were caught but not retained.

Biomass and Landings

Are landings and biomass related? Landings are dependent on biomass, management measures in the fishery, and fishing effort.

Data sources:
Biomass and landings from Status and Future Prospects for the Pacific Ocean Perch Resource in Waters off Washington and Oregon as Assessed in 2007, and the Alaska Fisheries Science Center

Important Dates

1956-1960 – Landings off the West Coast average slightly over 2,000 metric tons; catch is primarily from U.S. and Canadian fisheries
Early 1960s – USSR and Japan begin to target POP in the GOA; fishery develops rapidly
1960s – POP support major Japanese and Soviet trawl fisheries in the BSAI
1961 – Bering Sea catches peaks at 47,000 metric tons
Mid-1960s – Large catches of 5,000 to 20,000 metric tons off the West Coast, primarily by foreign vessels
1965 – Aleutian Islands catch peaks at 109,000 metric tons; catches peak in GOA at 350,000 metric tons
1966 – Landings peak at 15,000 metric tons off West Coast
Late 1960s – Overfishing results in decline in catches in GOA
1969 – POP stocks considered severely depleted throughout the Oregon-Vancouver Island region
1969-1994 – Moderate catches of between 1,100 and 2,200 metric tons off West Coast
1960s-1970s – Overfishing in BSAI results in decline in catches
1977 – Management of POP in waters off Washington, Oregon, and California shifts from the states to the Pacific Fishery Management Council; foreign fishery ends off West Coast with passage of the Magnuson Act
1978 – GOA catches only 8,000 tons
1981 – West Coast stock is depleted; PFMC adopts management strategy to rebuild POP stocks
1982 – Pacific Coast Groundfish FMP approved and implemented
Mid-1980s – BSAI stocks and catches decline and reach lowest levels
1985 – Catches reach a minimum in GOA, after foreign trawling in the GOA is prohibited
1990 – Domestic fleets replace joint-venture fisheries in BSAI
1992 – Limited entry program established for West Coast (Amendment 6 to the FMP)
1999 – POP declared overfished off West Coast
2003 – Pacific Fishery Management Council adopts rebuilding plan for POP, along with a vessel buyback program and depth-based management

Notes and Links

General Information:
AFSC Pacific Ocean Perch Research

Pacific Fishery Management Council's Backgrounder on Groundfish

Northwest Regional Office Groundfish Fishery Management

Groundfish of the Bering Sea and Aleutian Islands Area: Species Profiles

Groundfish of the Gulf of Alaska: A Species Profile

Fishery Management:
Pacific Coast Groundfish Fishery Management Plan

Bering Sea and Aleutian Islands Groundfish Fishery Management Plan and Appendix

Gulf of Alaska Groundfish Fishery Management Plan and Appendices

Stock Assessments:
Status and Future Prospects for the Pacific Ocean Perch Resource in Waters off Washington and Oregon as Assessed in 2007

2006 BSAI Pacific ocean perch stock assessment

2006 GOA Pacific ocean perch stock assessment

2005 GOA Pacific ocean perch stock assessment