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Western Atlantic Bluefin Tuna

Thunnus thynnus

Also Known As

  • Tuna
  • Bluefin tuna
  • Toro
  • Maguro
  • Giant bluefin
  • Northern bluefin tuna

U.S. wild-caught western Atlantic bluefin tuna is a smart seafood choice because it is sustainably managed under a conservation and management plan that allows limited harvest by U.S. fishermen.

Population

The population level is unknown for bluefin tuna in the western Atlantic.

Fishing Rate

At recommended level.

Habitat Impacts

Fishing gear used to catch bluefin tuna rarely contacts the ocean floor and has minimal impact on habitat.

Bycatch

Fishing gear used by U.S. fishermen to target schools of bluefin tuna is fairly selective, and allows for the live release of any unintentionally caught species.

  • Availability

    Year-round.

  • Source

    U.S. wild-caught from Maine to Louisiana.

  • Taste

    Bluefin has a distinctive flavor. With its high fat content, it is especially prized for sushi and sashimi. Cooking is generally not advised as it produces a strong fish taste and odor.

  • Texture

    Bluefin tuna flesh is the darkest and fattiest of any tuna. A higher fat content in bluefin tuna is equated with a higher-quality product. The flesh has the firmness and appearance of beef steaks.

  • Color

    Deep red when uncooked. When cooked, the meat is an off-white or ivory color.

  • Health Benefits

    Bluefin tuna is a very good source of protein, thiamin, selenium, vitamin B6, and omega-3 fatty acids.

The U.S. Fishery

Fishery Management

  • Effective conservation and management of highly migratory species like bluefin tuna require international cooperation as well as strong domestic management.
  • NOAA Fisheries, through the Atlantic Highly Migratory Species Management Division, manages the Atlantic bluefin tuna fishery in the United States, and sets regulations for the U.S. fishery based on conservation and management recommendations from the International Commission for the Conservation of Atlantic Tunas (ICCAT), consistent with applicable U.S. laws.
  • Managed under the 2006 Consolidated Atlantic Highly Migratory Species Fishery Management Plan and amendments:
    • Commercial and recreational fishermen must have a permit to harvest bluefin tuna.
    • Annual quota and subquotas.
    • Gear restrictions.
    • Time/area closures.
    • Minimum size limits.
    • Federal management for Atlantic tunas applies to state waters as well, except in Maine, Connecticut, and Mississippi. NOAA Fisheries periodically reviews these states’ regulations to make sure they’re consistent with federal regulations.
  • Regulations do not allow targeted fishing of bluefin tuna in the Gulf of Mexico, an important spawning area for the species.
  • NOAA Fisheries published several new regulations that are expected to reduce and improve accounting for bluefin tuna dead discards, including gear restricted areas and individual transferable quotas in the pelagic longline fishery, modified quota category allocations, and enhanced monitoring and reporting.
  • In 2000, the United States established the Dolphin-Safe Tuna Tracking and Verification Program to monitor the domestic production and importation of all frozen and processed tuna products nationwide, and to authenticate any associated dolphin-safe claim.

Harvest

  • ICCAT implemented harvest quotas for the western Atlantic bluefin tuna stock in 1982. Since then, catch has been relatively stable.
  • In 2016, U.S. commercial and recreational fishermen caught 1,026 metric tons of western Atlantic bluefin tuna (landings and dead discards).
  • In 2016, U.S. catch comprised 54 percent of total western Atlantic bluefin tuna catch and 5 percent of Atlantic-wide bluefin tuna catch (including the Mediterranean Sea).
  • Gear types, habitat impacts, and bycatch:
    • U.S. fishermen harvest bluefin tuna with handgear (rod-and-reel, handline, and harpoon) and purse seines.
    • Although fishermen are not allowed to use pelagic longline gear in the United States to target bluefin tuna directly, regulations allow them to retain a limited number of bluefin tuna caught incidentally while fishing for other species such as swordfish and yellowfin tuna.
    • Fishermen generally target schools of bluefin tuna, and their fishing gear is fairly selective and allows for the live release of any unintentionally caught species.
    • Fishing gear used to catch bluefin tuna rarely contacts the ocean floor and therefore has minimal impact on habitat.
    • NOAA Fisheries requires U.S. commercial fishermen who fish for yellowfin tuna, swordfish, and other species with pelagic longlines in the Gulf of Mexico to use "weak hooks," a type of hook designed to reduce the incidental catch and bycatch of Atlantic bluefin tuna.
    • Fishing for bluefin tuna in two known hotspots—Cape Hatteras, North Carolina and the Gulf of Mexico—is strictly regulated.
  • Commercial harvest:
    • In 2016, commercial landings of Atlantic bluefin tuna totaled 691 metric tons dressed weight and were valued at $11 million.
    • Ex-vessel prices depend on a number of factors, including the quality of the fish (e.g., freshness, fat content, method of storage), the weight of the fish, the supply of fish, and consumer demand.
    • Exports vary from year to year. In 2016, 43 percent of U.S. Atlantic bluefin catch was exported, mainly to sushi markets in Japan.
    • Exports of Atlantic bluefin tuna generally depend on the amount of commercial landings and Japanese yen/U.S. dollar exchange rates.
  • Recreational U.S. fishery:
    • Bluefin tuna may not be sold.
    • Bluefin tuna must be larger than 27 inches to be retained.
    • Depending on the recreational fishery (e.g., private vessels and charter/headboat vessels), limits on the amount and size of fish that fishermen can keep per fishing trip vary. For the latest information on current retention limits, visit the NOAA Fisheries HMS Permit Shop.
    • All released bluefin tuna must be released without removing the fish from the water and in a manner that will maximize its survival.
    • Recreational fishing for highly migratory species such as bluefin tuna provides significant economic benefits to coastal communities through individual angler expenditures, recreational charters, tournaments, and the shoreside businesses that support those activities.

The Science

Population Status

  • The 2017 stock assessment (pages 111 through 114) indicated that the western Atlantic bluefin tuna stock is not subject to overfishing.
  • Based on the information in the 2017 stock assessment, NOAA Fisheries has determined that the western Atlantic bluefin tuna stock has an unknown overfished status.
  • Scientists estimate that the western stock’s spawning stock biomass (a measure of the amount of bluefin that are able to reproduce) has been increasing since about 2004, after two decades of stability.
  • For the 2017 stock assessment, the scientists were unable to determine if the stock is rebuilt under the 20-year rebuilding plan. Based on this information, ICCAT adopted an interim conservation and management plan for the stock for 2018 through 2020.
  • Despite the longstanding uncertainty in estimating future recruitment, catch levels have been set at a level that is expected to support the maximum sustainable yield.
  • ICCAT selected a catch limit for 2018 through 2020 that is a 17% increase relative to the level in effect for 2015 through 2017. This level provides a buffer from the top end of the range in the scientific advice to ensure an additional layer of precaution given the uncertainties that are not fully accounted for in the assessment.
  • The Gulf of Mexico is the only known spawning area for the western stock of Atlantic bluefin tuna, and protecting these fish during spawning can help the long-term rebuilding of the depleted bluefin tuna population.

Location

  • In the western Atlantic, bluefin tuna are found from Newfoundland to the Gulf of Mexico.

Habitat

  • Atlantic bluefin tuna live near the surface in temperate waters but frequently dive to depths of 500 to 1,000 meters.
  • They are a highly migratory species. They can migrate thousands of miles across an entire ocean.
  • Tagging studies have indicated that bluefin tuna move across the east/west boundary in the Atlantic.
  • They tend to spawn in the same areas in the Gulf of Mexico.

Physical Description

  • Atlantic bluefin tuna have large, torpedo-shaped bodies that are nearly circular in cross-section.
  • They are the largest of the tuna species and can reach up to 13 feet and 2,000 pounds.
  • They have dark blue-black on the back and white on the lower sides and belly.
  • Atlantic bluefin tuna have colorless lines alternating with rows of colorless spots on their lower sides.
  • The second fin on their back (dorsal fin) is reddish brown, and they have short pectoral fins.
  • These characteristics separate this species from other members of the tuna genus, Thunnus.

Biology

  • Bluefin tuna grow more slowly than other tuna.
  • They have a long lifespan, up to 20 years or more and generally don’t spawn until they are about 8 years old. 
  • They spawn from mid-April to June, mainly in the Gulf of Mexico.
  • Females can produce up to 10 million eggs a year.
  • The eggs are fertilized in the water column and hatch in about 2 days.
  • Bluefin tuna are top predators.
  • Juveniles eat fish, squid, and crustaceans, and adults feed mainly on baitfish such as herring, bluefish, and mackerel.
  • Sharks, marine mammals (including killer whales and pilot whales), and large fish feed on bluefin tuna. Bluefish and seabirds also prey upon juvenile bluefin tuna.

Research

  • The ICCAT scientific committee typically assesses the abundance of Atlantic bluefin stocks every 2 to 3 years. The last report was in 2017 (pages 111 through 114).
  • Managers use the results of these stock assessments to develop new conservation and management measures as needed.
  • The United States supports research that concentrates on stock structure, migration, aging, spawning behavior, reproductive biology, and population modeling analyses.
  • NOAA Fisheries also collects data on bluefin tuna fishing efforts and catch from the United States to support ICCAT stock assessments and reports.
  • NOAA Fisheries’ scientists continue to study the possible effects of the 2010 Deepwater Horizon oil spill on Atlantic bluefin tuna, as the Gulf of Mexico is one of the only known spawning grounds for the western stock of Atlantic bluefin tuna.
  • Results of a 2014 study by NOAA and academic scientists indicate that crude oil can cause severe defects in large predatory fish like bluefin tuna.
  • In 2011, NOAA Fisheries conducted a scientific review of Atlantic bluefin tuna and determined that species protection under the Endangered Species Act was not warranted at that time.
  • Because the spawning season of many of these fish coincided with the 2010 Deepwater Horizon oil spill, young fish were potentially threatened.

Last updated: 12/04/2018