Arctic char

The Arctic char was initially scientifically described in the salmon genus Salmo as Salmo alpinus by Carl Linnaeus in the 1758 edition of Systema Naturae, which is the work that established the system of binomial nomenclature for animals. Meanwhile, he described Salmo salvelinus and Salmo umbla, which were later considered as synonyms of S. alpinus. John Richardson (1836) separated them into a subgenus Salmo (Salvelinus), which now is treated as a full genus. The genus name Salvelinus is from German – little salmon. 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 name torgoch, "red belly". Putative subspecies " In North America, three subspecies of Salvelinus alpinus have been recognized. • "S. a. erythrinus" is native to almost all of Canada's northern coast. This subspecies is nearly always anadromous. These scientific names are not generally accepted, however, as the names S. a. erythrinus and S. a. taranetzi usually refer to subspecies that are endemic to Siberia only. Morphs Arctic char is notable for exhibiting numerous, seemingly distinct morphological variants or 'morphs' throughout the range of the species. Consequently, Arctic char have been referred to as the "most variable vertebrate on Earth". 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 and large pelagic morph. 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. Hybrids Arctic char is known to produce hybrids with its congeners, Salvelinus namaycush (lake trout) and Salvelinus fontinalis (brook trout). 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 fertile while others are sterile. Sparctic char have been found locally in Sweden, for example in the Piteälven and Skellefteälven 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. == Distribution and habitat ==

It spawns in freshwater and its populations can be lacustrine, riverine, or anadromous, where they return from the ocean to their fresh water birth rivers to spawn. No other freshwater fish is found as far north; it is, for instance, the only fish species in Lake Hazen, which extends up to on Ellesmere Island in the Canadian Arctic. It is one of the rarest fish species in Great Britain and Ireland, found mainly in deep, cold, glacial lakes, and is at risk there from acidification. In other parts of its range, such as the Nordic countries, it is much more common, and is fished extensively. In Siberia, it is known as golets () and it has been introduced in lakes where it sometimes threatens less hardy endemic species, such as the small-mouth char and the long-finned char in Elgygytgyn Lake. 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 reproduce and overwinter. == Description ==

The Arctic char is closely related to both salmon and trout, such as the Atlantic salmon and lake trout, and has many characteristics of both. The fish is highly variable in colour, depending on the time of year and the environmental conditions of the lake where it lives. The appearance of Arctic char differs between populations. The dorsal side of the Arctic char is dark in its colour while the ventral varies from red, yellow, and white. 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 ' or ' 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. File:Salvelinus alpinus 252930820 (cropped).jpg|In Switzerland File:Salvelinus alpinus 217848936 (cropped).jpg|In Norway File:Salvelinus alpinus 256781750 (cropped).jpg|In Providensky, Russia File:Salvelinus alpinus 426756893 (cropped).jpg|In Austria ==Ecology==

Migration Arctic char can be anadromous, landlocked, or semi-anadromous. Arctic chars found north of 65°N latitude are generally anadromous. Dwarf Arctic char are also often cannibalistically consumed by giant Arctic char. There have been more than 30 species found in the stomachs of Arctic chars. 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 suspended 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 (Thysanoëssa). 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. == Reproduction ==

Spawning Spawning occurs over rocky shoals in lakes with heavy wave action and in slower gravel-bottom pools in rivers. As with most salmonids, vast differences in colouration and body shape occur between sexually mature males and females. Males develop hooked jaws known as kypes and take on a brilliant red colour. Females remain fairly silver. Males are polygamous in sexual nature each season. They will circumambulate the females by rubbing up against them slightly. As the female lays her eggs, the male fertilizes her, which takes place during the daylight hours. Most males set up and guard territories and often spawn with several females. The female constructs the nest, or redd. 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. Hatchlings Time to hatching varies, but usually occurs between two and three months, with the longest have been observed at five months. Arctic char ranges between 40 and 70 mg upon hatching. Hatchlings are immediately independent of parents at hatching, and stay at the bottom of the gravel till they are in length. Growth rates of Arctic char vary greatly. File:Salvelinus alpinus - Lake Inari population.JPG|A juvenile Arctic char File:Arctic charr at Llyn Padarn, Wales - torgoch yn Llyn Padarn.webm|Natural Resources Wales releases more than 5500 rare Arctic char in a lake in Wales, in a bid to preserve the species. File:Arctic charr- Llyn Padarn- Snowdonia- filmed Dec 2016.webm|Underwater video of char at Llyn Padarn, Wales == Human culture ==

Fisheries Numerous commercial fisheries are located in river systems throughout the Canadian Arctic, with the majority in Nunavut, such as the areas of Cumberland Sound and Cambridge Bay. There are also exploratory fisheries to examine potential for future commercial char fishing areas. 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." As food Commercial Arctic char typically weigh . The flesh is fine-flaked and medium firm. The colour is between light pink and deep red, and the taste is like something between trout and salmon. ==References==