Halibut
Halibut is the common name for three flatfish in the genera Hippoglossus and Reinhardtius from the family of right-eye flounders and, in some regions, and less commonly, other species of large flatfish.
This article is about the fish. For the United States Navy ships, see USS Halibut.The word is derived from haly (holy) and butte (flat fish), for its popularity on Catholic holy days.[1] Halibut are demersal fish and are highly regarded as a food fish as well as a sport fish.[1][2][3][4]
A 2018 cladistic analysis based on genetics and morphology showed that the Greenland halibut diverged from a lineage that gave rise to the Atlantic and Pacific halibuts. The common ancestor of all three diverged from a lineage that gave rise to the genus Verasper, comprising the spotted halibut and barfin flounder.[5]
Physical characteristics[edit]
The Atlantic halibut is the world's largest flatfish.[6] Halibut are dark brown on the top side with a white to off-white underbelly and have very small scales invisible to the naked eye embedded in their skin.[7] Halibut are symmetrical at birth with one eye on each side of the head. Then, about six months later, during larval metamorphosis one eye migrates to the other side of the head. The eyes are permanently set once the skull is fully ossified.[8] At the same time, the stationary-eyed side darkens to match the top side, while the other side remains white. This color scheme disguises halibut from above (blending with the ocean floor) and from below (blending into the light from the sky) and is known as countershading.
The IGFA size record for Halibut was apparently broken off the waters of Norway in July 2013 by a 234-kilogram (515-pound), 2.62-metre (8-foot-7-inch) fish. This was awaiting certification as of 2013.[9] In July 2014, a 219-kilogram (482 lb) Pacific halibut was caught in Glacier Bay, Alaska; this is, however, discounted from records because the halibut was shot and harpooned before being hauled aboard.[10]
Diet[edit]
Halibut feed on almost any fish or animal they can fit into their mouths. Juvenile halibut feed on small crustaceans and other bottom-dwelling organisms. Animals found in their stomachs include sand lance, octopus, crab, salmon, hermit crabs, lamprey, sculpin, cod, pollock, herring, and flounder, as well as other halibut. Halibut live at depths ranging from a few meters to hundreds of meters, and although they spend most of their time near the bottom,[1] halibut may move up in the water column to feed. In most ecosystems, the halibut is near the top of the marine food chain. In the North Pacific, common predators are sea lions, killer whales, salmon sharks and humans.
Sex determining genes[edit]
Halibut species vary in sex determination systems.[11] The Atlantic Halibut went down a purely XX/XY route, with the male being heterogametic, around 0.9 to 3.8 million years ago. The sex determining gene for the Atlantic Halibut is likely to be gsdf on chromosome 13.[11] The Pacific Halibut went down a ZZ/ZW route, with the female being heterogametic, around 4.5 million years ago.[11][12] The master sex determining gene of the Pacific Halibut is located on chromosome 9 and it is likely to be bmpr1ba.[13] The gene sox2 is likely to play the same role in the Greenland Halibut.
Nutritional value per 100 g (3.5 oz)
380 kJ (91 kcal)
0 g
0 g
Quantity
67 IU
Quantity
Quantity
80.3 g
49 mg