1. Largest Flatfish: Halibut are the largest flatfish in the world, with some individuals reaching lengths of over 8 feet (2.4 meters) and weighing more than 500 pounds (227 kilograms).Maximum weight, approx 500lbs, (230kg). You are not allowed to sport fish a halibut this size anymore. Conservation focus is on leaving the very large females to continue spawning.
2. Where? The largest Halibut in the world are found in BC and Alaska
3. Two Species: There are two main species of halibut: the Pacific halibut (Hippoglossus stenolepis) and the Atlantic halibut (Hippoglossus hippoglossus).
4. Migratory? Younger Halibut are very migratory and you often see them with red on their bellies,. The larger halibut are less migratory and stay closer to stay closer to spawning grounds. Some tagged fish recorded traveling over 2,000 miles.
5. Grow, Grow, Grow! Females grow faster and live longer than Males
6. Thousands of Eggs! A 50lb (23kg) Female can spawn around 500,000 eggs and a 250lb (113kg) over 4 million eggs, 8 times as many while being 5 times the size
7. Reproduction: Halibut spawning period is normally from November-February
8. Males mature 7-8 years, Females 8-12
9. Males between are mature in the 40-60lb range but are often caught under 25lbs.
10. The Maximum recorded halibut’s age was 55 years old (est)
11. Spawning Grounds: Halibut prefer deep, offshore areas with a muddy or sandy seabed, where their eggs can remain protected. Halibut typically spawn at depths ranging from 600 to 1,500 feet (183 to 457 meters), depending on the region and environmental conditions. These depths are often characterized by colder water temperatures between 37°F and 41°F (3°C to 5°C). These temps are essential for successful egg and larval development.
12. Floating Eggs: Halibut eggs and larvae are buoyant, floating in the water column until they hatch.
13. Juvenile Development: Juveniles live in shallow waters before migrating to deeper areas as they grow.
14. Eyes on One Side: Halibut begin life with eyes on both sides of their head, but as they mature, one eye migrates to the top side, making them a flatfish.
15. Coloration: Their upper side is dark brown to gray, camouflaging with the seabed, while their underside is white.
16. Halibut Cheeks: The cheeks of halibut are considered a delicacy, known for their tenderness and rich flavor.
17. “Chicken Halibut”: Halibut smaller than 20 pounds are often called “chickens” by anglers, while larger ones over 100 pounds are referred to as “barn doors.”
18. Sensitive to Pressure Changes: Halibut have specialized swim bladders that help them adapt to significant depth changes as they migrate or feed.
19. Daily Vertical Migration: Halibut sometimes move up the water column at night to feed, returning to the seafloor during the day.
20. What do Halibut and Chameleons have in common? Halibut can slightly adjust the pigmentation on their upper side to better blend with their environment.