7 Reasons Why Size Matters For Halibut | NOAA Fisheries

Skip to main content News 7 Reasons Why Size Matters for Halibut

May 14, 2019

Alaskan halibut are a remarkable fish. They can grow to be very large, and the bigger they are the better!

Feature Story | Alaska Flat fish swimming in open water near seafloor

Discover Some Fantastic Facts About the World’s Largest Flatfish

An Alaska Fisheries Science Center Researcher next to an Alaskan halibut.

An Alaska Fisheries Science Center Researcher next to an Alaskan halibut. Credit: NOAA Fisheries

  1. An Alaskan halibut can grow to be 8 feet long and 5 feet wide, and weigh 500 pounds.
  2. Because of their size, adult halibut have few predators—mainly sharks, marine mammals, and humans.
  3. Their large size and delectable white meat make halibut a prized target for both commercial and sport fishermen, as well as an important subsistence resource. Halibut is one of Alaska’s most valuable fisheries.
  4. Huge halibut are called "barn doors"; small halibut are "chickens."
  5. "Barn door" halibut are typically females. Females grow much larger than males, which rarely reach a length of 3 feet.
  6. Mother halibut get more prolific as they get bigger. A 50-pound female produces about 500,000 eggs, and more eggs mean more future halibut to catch! A 250-pound female can produce 4 million eggs!
  7. Halibut have been getting smaller for their age since the 1970s. By the 2000s, an average 12-year-old halibut weighed half as much as one in the 1980s. The reasons for the decrease in size are unknown, but competition for food, climate effects, and fishing effects are possible causes.

More Information

  • Alaska Fisheries Science Center
  • Pacific Halibut
  • NOAA Fisheries Fish Watch: Pacific Halibut
  • International Pacific Halibut Commission

Recent News

Feature Story

Seafood Tips from the People Bringing You America's Seafood (Part 2)

Feature Story , Alaska Pacific Islands West Coast National Alaska Pacific Islands West Coast National A grid of two rows of three photos each, with a text box "meet the people brining our nation seafood". The top row: A man in a hat holding two plates of seafood in front of a Fish Market storefront (left); A man kneeling on a tarp in an estuary with a handfull of small oysters (middle); A man in a teal shirt smiling with a beach in the background (right). In the bottom row: A family on a small boat labaled Farm Stand (right); a woman in a chef's apron and shirt holding up a salmon standing on a rocky coastl Credit: NOAA Fisheries and Partners Feature Story

Snow Crab Collapse Linked to Energetic Limitations During a Marine Heatwave

Feature Story , Alaska Alaska On the back deck of a fisheries survey vessel, two adult snow crabs on top of a blue plastic tote. Snow crabs sampled during the 2024 eastern Bering Sea bottom trawl survey. Credit: NOAA Fisheries / Erin Fedewa Feature Story

NOAA Fisheries Seeks Recommendations for Restoring American Seafood Competitiveness

Feature Story , Alaska New England/Mid-Atlantic Pacific Islands Southeast West Coast National Alaska New England/Mid-Atlantic Pacific Islands Southeast West Coast National Commercial fishing boats lined up in Sitka, Alaska. Commercial fishing boats lined up in Sitka, Alaska. Credit: Shutterstock. More News

Last updated by Alaska Fisheries Science Center on March 28, 2022

Alaska Groundfish Research Halibut

Tag » How Big Do Halibut Get