Product Code Database
The Arctic char or Arctic charr ( Salvelinus alpinus) is a cold-water fish in the family Salmonidae, native to , as well as Arctic and subarctic coastal waters in the Holarctic realm.
The English name is thought to derive from Old Irish ceara/ cera meaning "blood red", referring to its pink-red underside. This would also connect with its Welsh language name torgoch, "red belly".
These scientific names are not generally accepted, however, as the names S. a. erythrinus and S. a. taranetzi usually refer to subspecies that are Endemism to Siberia only.
In Iceland, Þingvallavatn is noted for the evolution of four morphs: small Benthic zone, large benthic, small Limnetic zone and large limnetic.
In Svalbard, Norway, Lake Linnévatn on Spitsbergen has dwarf, 'normal', and normal-sized anadromous fish, and Lake Ellasjøen on Bear Island has a dwarf, small Littoral zone and large Pelagic zone morph. In 2004, a previously unknown species closely related to Arctic char were discovered swimming near the bottom of Lake Tinn in Norway at a depth of ; The light-colored, translucent fish is up to long and lacks a swim bladder.
In Sweden three morphs are usually recognised: storröding, större fjällröding and mindre fjällröding. Wherever these types occur together in the same lake storröding is the largest. Contrary to what the name may suggest when större fjällröding and mindre fjällröding are found together mindre fjällröding tend to be the largest morph. Even within storröding morphs can be found; for example the Sommen charr of Sommen tend to grow faster and reach sexual maturity later than the char from Lake Vättern.
The sparctic char is the intrageneric hybrid between Arctic char and brook trout. Sparctic char grows faster than either parent species, are stronger and healthier, and are thus popular for sports fisheries. Some of these hybrids are Fertility while others are Infertility Sparctic char have been found locally in Sweden, for example in the Pite River and Skellefte River Rivers in the northern part of the country, though are believed to be relatively uncommon.
There has been no formal naming of the hybrid between Arctic char and lake trout as few studies have been done in regard to this hybridization.
Arctic char is also found in Lake Pingualuit in the Ungava Peninsula, Quebec, a lake situated in an impact crater formed roughly 1.4 million years ago. Since the last glaciation, changing water levels are believed to have connected the lake with glacial runoff and surrounding streams and rivers, allowing char to swim upstream into the lake. Arctic char is the only fish found in the lake, and signs of fish cannibalism have been found. Arctic char exhibits a mostly circumpolar distribution. There is no other species of freshwater fish found at a higher latitude. Arctic char is native to Arctic and subarctic coasts and lakes of high elevations. In general, it has been observed in the Canadian Arctic, Greenland, Iceland, Scandinavia, Siberia, and Alaska.
Anadromous Arctic chars migrate to the sea annually in mid-June to mid-July. After about two months, they return to fresh water to Reproduction and Overwintering.
Arctic char has a distinct size dimorphism, dwarf and giant. Dwarf Arctic char weigh between and average a length of , while giant Arctic char weigh between and average in length. Individual fish can weigh or more with record-sized fish having been taken by anglers in Northern Canada, where it is known as iqaluk or tariungmiutaq in Inuktitut. Generally, whole market-sized fish are between . Male and female Arctic char are the same size.
The flesh colour can range from a bright red to a pale pink.
Arctic chars found north of 65°N latitude are generally anadromous. Anadromous Arctic chars spend their juvenile years in fresh water, and once mature, migrate annually to the marine environment. The first migration of Arctic char has been found to occur between 4 and 13 years of age. When in the marine environment, Arctic chars inhabit and Intertidal zone areas. They migrate back to frozen lakes at the end of summer.
Generally, Arctic char inhabits shallow waters, rarely swimming deeper than depth. An exception to this applies to landlocked Arctic chars, which often swim much deeper in the summer in order to occupy colder waters. Dwarf Arctic chars are more common in landlocked populations as a result of scarce resources (immense competition).
Arctic char often demonstrates crypsis when defending from their predators. It will appear darker in its freshwater environments and lighter in its marine environments. Additionally, some juveniles have highly sensitive recognition of predator odours and respond to chemical cues from different fish predators.
During late spring and summer, Arctic char feeds on insects found on the water's surface, salmon eggs, snails and other smaller crustaceans found on the lake bottom, and smaller fish up to a third of its size. During the autumn and winter months, it feeds on zooplankton and freshwater shrimps that are Plankton in the lake, and also occasionally on smaller fish.
The marine diet of Arctic char consists mostly of a copepod species ( Calanis finmarchicus) and krill ( Thysanoessa). Lake-dwelling Arctic chars feed mostly on insects and zoobenthos. Some giant Arctic chars have been recorded as cannibals of their young as well as dwarf Arctic chars.
A female anadromous char usually deposits from 3000 to 5000 eggs. Arctic char do not die after spawning like Pacific salmon, and often spawn several times throughout their lives, typically every second or third year. Young Arctic char emerge from the gravel in spring and stay in the river from 5 to 7 months, or until they are about in length. Sexual maturity in Arctic char ranges from 4 to 10 years old and in length.
Arctic char fisheries are important for the Inuit and in the subsistence economy of many circumpolar people. The fisheries are concentrated near communities and are predominately conducted using Gillnetting. In 2004, it was estimated that the subsistence harvest in the Cambridge Bay area was about 50% the size of the commercial harvest.
Arctic char was first investigated because they expected it to have low optimum temperature requirements and would grow well at the cold water temperatures present in numerous areas of Canada. It could be an alternate species to Rainbow trout, and could provide producers with a different niche in the marketplace. The initial research efforts concentrated on identifying the cultural needs and performance characteristics of the species. The Freshwater Institute was responsible for distributing small numbers of Roe to producers in Canada; these producers in return helped determine the suitability of Arctic char in a commercial setting. Commercial Arctic char breeding stocks have now been developed largely from these sources.
Arctic char eggs are hatched within specialized hatchery facilities. The young fish remain in the hatchery until they reach about , and are then transferred to tanks each capable of holding 5000 fish. Arctic char first exhibits a rapid growth spurt during this phase, reaching its market weight of within a year. They are fed dried pellets consisting mainly of fish meal and fish oil from forage fish that are too small and bony for human consumption. are also added, giving Arctic char its characteristic coral colouration. in naturum Sommen]]The land-based Arctic char farming systems are among the most environmentally responsible fish farming designs. They remove Particulates and effluent prior to releasing water from the fish tanks into the environment. Sludge removed from the water is used to fertilize terrestrial crops. Leftovers from fish processing may be incorporated into dog food or delivered to local compost facilities.
In 2006, Monterey Bay Aquarium Seafood Watch program added farmed Arctic char as an environmentally sustainable Best Choice for consumers, stating: "Arctic char use only a moderate amount of marine resources for feed" and that they "are farmed in land-based, closed systems that minimize the risk of escape into the wild."
|
|
