Hippoglossus stenolepis, the Pacific Halibut, is a species of righteye flounder. The Pacific halibut is found on the continental shelf of the North Pacific Ocean and Bering Sea. Fishing for the Pacific halibut is mostly concentrated in the Gulf of Alaska and the Bering Sea, off the west coast of Canada. Small halibut catches are reported in coastal Washington, Oregon, and California. Halibut are demersal, living on or near the bottom of the water and prefer water temperatures ranging from 3 to 8 degrees Celsius (37.4 to 46.4 degrees Fahrenheit). Pacific halibut belong to the family Pleuronectidae. They are among the largest teleost fishes in the world. From November to March, mature halibut concentrate annually on spawning grounds along the edge of the continental shelf at depths from 183 to 457 m (600 to 1,499 ft). Halibut are strong swimmers and are able to migrate long distances. Pacific halibut have diamond-shaped bodies. They are more elongated than most flatfishes, the width being about one-third of the length. It has a high arch in the lateral line over the pectoral fin, and a crescent-shaped tail, which is different from other flat fishes. Small scales are embedded in the skin. Halibut have both eyes on their dark or upper sides. The color on the dark side varies, but tends to assume the coloration of the ocean bottom. The underside is lighter, appearing more like the sky from below. This color adaptation allows halibut to avoid detection by both prey and predator. They are one of the largest flatfish, and can weigh up to 500 pounds and grow to over 8 feet long. Halibut growth rates vary depending on locations and habitat conditions, but females grow faster than males. The oldest recorded female and male were 55 years old. The largest recorded sport-caught halibut was 459 lb (208 kg) near Unalaska, AK, in 1996.