Pacific Halibut

About the Species

Pacific halibut is the largest species of flatfish. It is native to the North Pacific Ocean and it is fished by commercial, recreational, and subsistence fishermen. Huge Pacific halibut, sometimes called "barn doors", can attain a length of over 8 feet and a width of over 5 feet. Halibut are born swimming like salmon, with eyes on either side of their head. As they grow (by the time they are six months old), one eye migrates to the right side and the young halibut begin swimming sideways, with both eyes on the top of their bodies. Their large size and delectable meat make them a popular and prized target for both sport and commercial fishermen.

U.S. wild-caught Pacific halibut is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations.

Status

• According to the 2018 stock assessment, Pacific halibut are not overfished, and are fished at recommended levels that are set by the International Pacific Halibut Commission. The population was declining from 1997 until 2013. It has been increasing since 2013.

Appearance

• Pacific halibut have flat, diamond-shaped bodies.
• They swim sideways, and the upper side is typically mottled gray to dark brown, which helps them blend in with sandy or muddy bottoms. Their underside is typically white.
• Both of their eyes are on the upper side of their body.
• Their scales are small and buried in the skin, giving them a smooth appearance.

Biology

• Pacific halibut are one of the largest flatfish – they can weigh up to about 500 pounds and grow to more than 8 feet long.
• Males tend to be smaller than females.
• Males sexually mature when they are 8 years old, and females are able to reproduce by the age of 12.
• They spawn during the winter in deep water along the continental slope, mainly in the Bering Sea, Aleutian Islands, Gulf of Alaska, and south to British Columbia.
• Depending on their size, females can have between 500,000 and 4 million eggs.
• Scientists believe females release their eggs in batches over several days during the spawning season. Eggs hatch after 12 to 20 days, dependent on water temperature.
• The larvae slowly float close to the surface, where they remain for about 6 months until they reach their adult form and settle to the bottom in shallow water.
• Larval Pacific halibut feed on zooplankton (tiny floating organisms).
• Juveniles eat small crustaceans and other organisms that live on the seafloor.
• Halibut live to be relatively old – the oldest halibut on record was 55 years old, but halibut over age 25 are rare.
• Adults aggressively prey on a variety of groundfish, sculpins, sand lance, herring, octopus, crabs, clams, and occasionally smaller Pacific halibut.
• Marine mammals and sharks sometimes eat Pacific halibut but, due to their large size, adult Pacific halibut are rarely preyed upon by other fish.

Where They Live

• Pacific halibut are found in coastal waters from Santa Barbara, California, to Nome, Alaska.
• They are most common in the central Gulf of Alaska, particularly near Kodiak Island. 

Management

• Since 1923, the United States and Canada have coordinated Pacific halibut management through a bilateral commission known as the International Pacific Halibut Commission (IPHC). NOAA Fisheries and the North Pacific and Pacific Fishery Management Councils are responsible for allocating allowable catch among harvesters in the U.S. fisheries.
• IPHC:
  • Using the latest scientific information on the abundance and potential yield of the Pacific halibut stock, establishes catch limits annually for fisheries in U.S. and Canadian waters.
  • Sets the catch limits at a level that will ensure the long-term welfare of the Pacific halibut stock.
  • Sets the dates for the fishing season, which usually spans from March to November and is closed the rest of the year when Pacific halibut spawn.
  • The commercial fishery has a minimum size requirement to protect juvenile Pacific halibut.
• In Alaska, the North Pacific Fishery Management Council is responsible for allocating the catch limits among users and user groups fishing off Alaska and developing regulations for the fishery, in line with IPHC recommendations. NOAA Fisheries is responsible for implementing and enforcing these regulations:
  • Individual fishing quota program, which allocates the total allowable catch among fishing vessels and individual fishermen. With their catch set, fishermen have the flexibility to harvest their quota anytime, creating a safer, more efficient, more valuable, and environmentally responsible fishery.
  • Community development quota program, which allocates a percentage of the total allowable catch to eligible western Alaska villages to allow them to participate and invest in fisheries in the Bering Sea and Aleutian Islands and to support sustainable economic and community development in western Alaska.
• For waters off the U.S. West Coast, the Pacific Fishery Management Council is responsible for allocating the catch limits among users and user groups fishing off the West Coast and developing regulations for the fishery, in line with Commission recommendations. NOAA Fisheries is responsible for implementing and enforcing these regulations:
  • Establish regulations for Pacific halibut fisheries in U.S. waters off Washington, Oregon, and California (known as IPHC Regulatory Area 2A).
  • The IPHC sets the catch limit for Pacific halibut in this regulatory area, and the Pacific Council allocates the catch among the following user groups: non-tribal commercial (incidental salmon troll fishery, directed longline Pacific halibut fishery, and incidental longline sablefish fishery), sport, and treaty Indian commercial and ceremonial-and-subsistence.
• The Pacific Council describes the division of Pacific halibut catch each year in the Pacific Halibut Catch Sharing Plan for Area 2A.