Since 1994, management plans and license conditions require the release of halibut less than 81 cm. Annual TACs have increased several times since 2000. In 1999, recommendations made by the Fisheries Resource Conservation Council (FRCC) resulted in an increase in the TAC from 850 to 1000 t. The TAC was reduced to 1500 t in 1994, and was further reduced to 850 t in 1995. In 1988, a total allowable catch (TAC) of 3,200 t was set for 3NOPs4VWX5Zc. Until 1988, the halibut fishery was unregulated. Within the management unit 3NOPs4VWX5Zc, which encompasses the Scotian Shelf and southern Grand Banks, halibut is fished mostly along the edges of the continental shelf mainly by longliners using bottom hook-and-line gear. Spawning location and times are not known, but anecdotal accounts by halibut fishermen indicate that spawning by Atlantic halibut likely occurs in deep water (300–700 m) during winter months between December and March. Age at maturity is uncertain, but length at maturity has been estimated to be about 115 cm for females and about 75 cm for males. The maximum size for females (200 cm) is much greater than males (140 cm). Growth of males and and females from the Scotian Shelf and southern Grand Banks is similar up to about 7 or 8 years (~100 cm), after which point male growth slows, while female growth continues at the same rate up to 20 years. Small halibut (<30 cm) feed on hermit crabs, prawns, small crabs, and mysids, while those larger than 70 cm consume flatfish ( Hippoglossoides platessoides), redfish ( Sebastes spp.), and pollock ( Pollachius virens). As the size of halibut increases, prey selection shifts from invertebrates to fish. Gut content information indicates main prey items are benthic dwelling or demersal in nature. Apart from its size, the Atlantic halibut can be distinguished from most other species of flatfish by its concave tail. The mouth has a very large gape extending to the midline of the eyes and is armed with numerous sharp curved teeth. The blind side is usually white in young fish but becomes mottled with grey or even cherry red in older, larger fish. The halibut's coloration, which occurs only on the eyed side of the body, varies from greenish brown to very dark chestnut brown. They are flattened from side to side and swim with the left side facing the bottom and the right or eyed side facing the surface. Halibut belong to the family Pleuronectidae whose members usually have both eyes on the right side of their bodies with the left side being totally blind. Larger halibut are found in a larger depth range, and are also found in deeper water in winter. On the Scotian Shelf and southern Grand Banks, halibut are most abundant at depths of 200–500 m in the deepwater channels running between the banks and along the edge of the continental shelf. Halibut are demersal, living on or near the bottom, with a temperature preference of between 3 and 5☌. Their geographic range in the Northwest Atlantic extends from the coast of Virginia in the south to the waters off Disko Bay, Greenland in the north, although they are now commercially extinct in US waters and are rare south of the Grand Banks. Growing to more than 2.5 m in length and exceeding 300 kg in weight, Atlantic halibut ( Hippoglossus hippoglossus) is the largest, most widely-ranging and commercially-valuable groundfish in the Atlantic Ocean. Atlantic halibut may grow to a length of more than two metres though they typically weigh less than 100 kg. Their mouths are very large and have numerous sharp curved teeth. Juveniles might be slightly spotted or flecked and have white undersides, which become mottled with grey or reddish spots as they mature. They are greenish-brown to almost black on their eyed side. Species DescriptionĪtlantic halibut have a compressed, oval-shaped body and usually have both eyes on the right side of their bodies with the left side being totally blind. Atlantic halibut are fished commercially. In the northeast, Atlantic halibut range from the Bay of Biscay to Spitsbergen and the Barents Sea. Significant numbers swim off the coasts of Greenland, Newfoundland and Labrador, the Gulf of St. In the northwestern Atlantic, populations are found from the coast of Virginia to as far north as the Arctic Circle. Atlantic halibut are distributed widely throughout the northern Atlantic.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |