Halibut

Lore & Background

Halibut are symmetrical at birth with one eye on each side, but during larval metamorphosis one eye migrates to the other side. Their top side is dark brown, underbelly white, providing countershading camouflage. They feed on almost any fish or animal they can fit into their mouths, including sand lance, octopus, crab, salmon, and even other halibut. In most ecosystems, halibut are near the top of the marine food chain; in the North Pacific, predators include sea lions, killer whales, salmon sharks, and humans.

The North Pacific commercial halibut fishery dates to the late 19th century and is one of the region's largest and most lucrative. Long-line fishing predominates, using chunks of octopus on circle hooks. For most of the modern era, the fishery operated as a derby with short open periods, leading to unsafe fishing and market gluts. In 1995, US regulators allocated individual fishing quotas (IFQs) to existing participants, improving safety and product quality.

The Atlantic halibut has been a major target since the 1840s, with overfishing causing depletion in Georges Bank by the 1850s–1860s and extending to the Canadian Arctic by 1866. The American fishing industry collapsed in the 1940s, and Canadian fishery declined in the 1970s–1980s. The population rebounded briefly before collapsing in the 1990s, then recovered from a low in the early 2000s, but remains less abundant than in the early 1800s.

Reader's Guide

Halibut are significant as a major commercial and sport fishery species, particularly in the North Pacific and North Atlantic. Their management illustrates the evolution from derby-style fishing to individual fishing quotas, which improved safety and market stability. The species' slow maturation—not reproducing until age eight—necessitates international management to prevent overfishing. The Atlantic halibut's history of depletion and partial recovery serves as a case study in fishery collapse and rebound. The Pacific halibut and Greenland halibut have not experienced the same fragmentation, and their populations remain larger. The halibut's unique physical characteristics, including eye migration and countershading, make it a notable example of flatfish adaptation. The ongoing debate over which species grows largest, and the pending record of a 234 kg fish, highlight the halibut's status as the world's largest flatfish.

Did You Know?

• The word 'halibut' comes from 'haly' (holy) and 'butte' (flat fish), due to its popularity on Catholic holy days.
• Halibut are symmetrical at birth, but one eye migrates to the other side during larval metamorphosis.
• A 233.5 kg (515 lb) halibut caught off Norway in July 2013 holds the official all-tackle world record.
• Both Atlantic and Pacific halibut use an XX/XY sex determination system.