FishWatch

Harvesting arrowtooth flounder

Fishermen mainly use bottom trawl gear, including specialized flatfish trawls, to catch arrowtooth flounder. Bottom trawlers tow a funnel-shaped net on or near the ocean floor, collecting fish in the narrow part of the net (the cod-end). Trawl doors keep the net open, and a weighted rope (called a footrope) keeps the net close to the floor. The trawl doors and footrope of the net can contact and impact the ocean floor. In general, arrowtooth flounder live on sandy or sand/gravel habitats; these soft bottom habitats are usually more resilient than other habitats to trawling impacts.

In Alaska, NOAA Fisheries scientists and the flatfish fishing industry collaborated to develop changes to fishing gear that would reduce effects of flatfish trawling on seafloor habitats of the eastern Bering Sea shelf. The modified gear they developed – Bering Sea flatfish gear – not only reduced impacts to sea floor habitat and the animals living there but also reduced the fishery’s impacts on crabs. In the Bering Sea and Aleutian Islands area, flatfish fishermen are now required to use this modified fishing gear. Halibut are sometimes incidentally caught in this fishery, but there is a cap on the number of halibut that can be incidentally caught in the fishery. When this limit is reached, the fishery is shut down.

Off the West Coast, fishermen catch arrowtooth flounder with a selective flatfish trawl, a design that substantially reduces catches of rockfish species while more efficiently catching the targeted flatfish species. Some rockfish, including canary rockfish (an overfished groundfish), are still unintentionally caught, but management caps the amount of rockfish that can be incidentally caught in the fishery. To protect sensitive fish habitat off the West Coast, gear restrictions limit where flatfish fishermen can fish.

Management

Who’s in charge? NOAA Fisheries and the North Pacific and Pacific Fishery Management Councils.

Current management:

Alaska: Gulf of Alaska and Bering Sea and Aleutian Islands Groundfish Fishery Management Plans Although arrowtooth flounder are not currently a major commercial seafood species in Alaska fisheries, the species has been included in these fishery management plans because of their importance to the ecosystem (it’s a very abundant flatfish and an important part of the food chain as both predator and prey) and growing commercial interest. There is a limit on the total amount of arrowtooth flounder that can be harvested each year; however, annual harvests have consistently been below this level.

West Coast: Groundfish Fishery Management Plan. (Arrowtooth flounder are often caught along with several different groundfish species; they are managed with 90 other species that also live on or near the bottom.)

• General regulations include groundfish harvest levels and fishing restrictions (trip limits, season lengths, gear restrictions such as minimum mesh size for nets, etc.). NOAA Fisheries publishes these regulations every other year, before the start of the fishing year on January 1. NOAA Fisheries may amend these regulations in-season to correct mistakes or revise management measures according to recommendations from the Pacific Fishery Management Council.
• A variety of closed areas affect both West Coast groundfish fisheries and fisheries that may take groundfish incidentally. Areas are closed to reduce bycatch of overfished groundfish species and protect groundfish habitat. Managers use a vessel monitoring program to monitor fishing activity and ensure vessels are complying with these closures.
• All vessels fishing for groundfish off Washington, Oregon, and California must have a federal limited entry permit. With a finite number of permits available (about 400), this program controls the size of the groundfish fishing fleet by limiting the number of fishing vessels and limiting vessel length.
• As of January 2011, the West Coast groundfish trawl fishery is now managed under a trawl rationalization catch share program. Under this new program, managers establish annual catch limits based on the health of each fish stock. They then allocate a share of this catch limit to individual fishermen or groups of fishermen. These fishermen can decide how and when to catch their share – preferably when weather, markets, and business conditions are most favorable, allowing the fishery the flexibility to be more environmentally responsible, safer, more efficient, and more valuable. Observers monitor 100 percent of the fishing trips, which helps reduce bycatch and provide better data for future stock assessments.

Annual Harvest

Most of the global supply of arrowtooth flounder is harvested in Alaska fisheries. Although arrowtooth flounder are a low-value fish, fishermen have recently been retaining more of the arrowtooth they catch – up to about 80 percent in Alaska. Catches have been higher in recent years because arrowtooth flounder are more abundant, resulting in higher incidental catch in other fisheries, in addition to increased marketing efforts for arrowtooth fish meal and surimi. Preliminary reports of catch in 2011 totaled nearly 16,000 tons in the Bering Sea and Aleutian Islands and over 23,200 tons in the Gulf of Alaska.

Around 2,000 to 4,000 metric tons of arrowtooth flounder are annually harvested off the U.S. West Coast. In particular, it is an abundant and commercially important groundfish species off Washington; however, the catch is constrained by efforts to rebuild canary rockfish, an overfished species.

Economy

Several food-grade additives have been successfully used to inhibit the enzymatic breakdown of arrowtooth’s flesh when heated. These discoveries have enabled a targeted fishery in the Kodiak Island area for a number of marketable products. Most arrowtooth flounder are processed as headed and gutted and sent to China for re-processing. The primary product for arrowtooth flounder is the frill, the fleshy fins used for engawa (a premium sushi usually made from halibut or Greenland turbot, but more affordable using arrowtooth flounder). A large portion of the arrowtooth flounder exported to China are processed into fillets and re-imported to U.S. markets as inexpensive flounder. Some arrowtooth flounder processed in Japan are also sold as fillets in the Japanese market and have even recently shown up in European markets.

Attempts have also been made to expand production levels of surimi from arrowtooth flounder. Surimi is the processed fish used to make imitation crab. While the economic feasibility of large-scale commercial production of arrowtooth surimi is still uncertain, the current worldwide surimi supply shortage caused by reductions in the U.S. pollock quota may make the abundant arrowtooth flounder an increasingly attractive alternative raw material for the production of surimi seafood products.