Arctic Char

The most northern freshwater fish Salvelinus alpinus is variously known as Arctic char and Arctic charr (English), omble chevalier (French), eqaluk (Greenlandic), iqaluppik (Inuktitut), bleikja (Icelandic), tarr (Gaelic), r0ye (Norwegian), ravdo, rauta, and rautu (Saami), roding (Swedish), nieria (Finnish), golets, paliya, and arkticheskii golets (Russian), and khivko and noratkan (Evenki). It belongs to the Salmonidae family, and is related to salmon and trout.

Char are typically troutlike in shape (long, torpedolike body) with very small scales. The front edge of the pectoral, pelvic, and anal fins is white; the back and the dorsal fin do not have a vermicular (wormlike) pattern, as do brook char (S. fontinalis) and lake char (S. namaycush). The body can be extremely colorful, with a great deal of variation in appearance depending on its life cycle, locality, and sex. The back is grayish with a blue, green, or brown coloration, while the underside can be red, rose, orange, yellow, or silvery white. Light-colored spots are scattered on the back and sides. This great variation in appearance has led to confusion in Arctic char systematics and some confusion with the Dolly Varden char (S. malma), which is excluded here.

Arctic char populations have two basic forms depending on life history: anadromous (feeding in the sea and migrating to fresh water to breed) and landlocked. Both forms are widely distributed in a circumpolar pattern. However, while the anadromous form is restricted to the Arctic, landlocked char are also found in more southern latitudes, in Europe, Russia, Alaska, Canada, and the United States. The anadromous form occurs from northern Norway through northern Eurasia (except the White Sea) to the Chukotka Peninsula; from northern Canada to Newfoundland; Hudson Bay (excluding James Bay); Greenland; Iceland; and Svalbard (but not Alaska) (maps of Arctic char distribution in Alaska before and after 1992 differ considerably because of improved methods of distinguishing Dolly Varden from Arctic char). The landlocked form is found in all territories with the anadromous form, plus B0rn Island; Jan Mayen; Faroe Islands; Ireland; United Kingdom; the Alps of France, Switzerland, Germany, and Austria; Scandinavian peninsula; Finland; Karelia; Putorana Plateau; Transbaikalia; Magadanskaya Oblast' and Chukotka; Kamchatka (only in two lakes); Alaska; Québec; New Brunswick; and Maine.

Arctic char vary considerably in body size between populations. In the 1930s, professional fishermen in Novaya Zemlya are believed to have caught char up to 1 m in length and 16 kg in weight. Johnson (1980) shows a photograph of three char caught in Greiner Lake (Victoria Island, Canada), the largest of which has a fork length (length from the tip of the snout to the fork in the tail) of 80.6 cm and a weight of 5.75 kg. In 1962, a specimen of 75.0 cm in body length (from the tip of the snout to the end of the last scale) and 6.43 kg in weight was caught in Khantaiskoe Lake (Putorana Plateau, Taymyr Autonomous Okrug). Professional hunters told the author that they have occasionally caught large individuals in this lake, each weighing more than 20 kg, and these rare catches were generally in winter. At the other end of the scale, a population can be dwarfed. These fish remain very small even as adults, often being less than 20 cm in total length (from snout tip to tail tip). In July 1985, Nyman (1987) sampled 30 individuals from a brook in Sweden called Vastra Trullgrav. They averaged 9.1 cm in total length, the largest fish being 11.7 cm total length and the oldest fish being aged 10+ years (in its 11th year).

The Arctic char life history varies between populations and also between individuals within populations. After hatching, young anadromous char remain in the lake (if hatched in a river, the young move to the lake) for two to nine years before making their first sea migration. Called smolts, they become silvery in color. The downstream migration occurs between the end of May and July, and they stay in the sea for only two to three months before migrating upstream between July and September. They overwinter in the lake and repeat the migration cycle the following spring. After several migrations, they become spawners. Almost all spawn-ers have a very strong homing instinct, but the homing behavior does not seem to be so strong in nonspawn-ers, which may swim up any river with a suitable overwintering lake. Spawning occurs in lakes or rivers, generally between October and February, and the char lay eggs in redds—hollows in the substrate used for spawning. The adults survive after spawning and will repeat the cycle the following year.

Although the landlocked form does not migrate to the sea, their life histories are just as variable. One or more Arctic char populations may occur in a single lake. Each population can be characterized by morphology, genotype, feeding behavior, or spawning ground. The fish may be benthic (feeding on bottom-living animals), pelagic (feeding on plankton), or fish predators. In some cases, a population of dwarfed char occurs. These fish have neither commercial nor fishing value. There seem to be several factors that result in dwarfism, but the mechanisms are not yet fully understood. For some cases, however, a plausible explanation is simply that the fish are too numerous, and so food is scarce. Their growth is very limited or even prevented. If this is the case, removing a significant number of fish individuals artificially will improve the fish growth.

High in the Arctic, where both anadromous and landlocked forms occur, the life pattern can be intermediate between the two forms. In some populations, there is an interval of a year between the spawning migration and reproduction; the spawners wait for a year in fresh water before spawning. The variability and apparent complexity of the life cycles result in the very wide ecological niche of Arctic char, which adapts to a wide range of habitats in the Arctic environment. Nevertheless, certain conditions seem to be necessary: cold oxygen-rich water, still water, and fresh water that does not freeze in winter. This is why Arctic char are not generally found in rivers (except during migration or spawning), in shallow lakes, or in the sea in winter.

Arctic char are a valuable commercial and food resource for northern peoples. There are over 50,000 populations of Arctic char in the world with a catch of around 3000 tons a year. Since the 1980s, artificial rearing of Arctic char has been well developed, particularly by Iceland and Norway, and such fish have been available on the fish market all year round since the 1990s.

In catching Arctic char today, gill nets and spinning fishing are the most widely used techniques. Canadian Inuit traditionally used stone weirs to corral the fish; the Arctic char were trapped in the weirs and speared.

Harpoons were also used in certain areas, a technique requiring great skill. In Baffin Island, some Arctic char become naturally trapped during upstream migration. In spring, local people harvested these frozen fish through cutting holes in the ice. In sport fishing, char are generally caught by simple lure fishing, usually with a spinner or spoon. Fly fishing is also possible, but it depends on place and time. Since the 1980s, some sport-fishing tourism has been developed for this fish in northern Canada. There, fishing regulation and protection measures are strictly enforced on these sport fisheries in order to sustain the local economy that is dependent on Arctic char.

Yoichi Machino

Further Reading

Balon, Eugene (editor), Charr: Salmonid fishes of the Genus

Salvelinus, The Hague: Dr. Junk, 1980 Frost, Winifred, "Breeding habits of Windermere charr, Salvelinus willughbii (Gunther) and their bearing on specia-tion of these fish." Proceedings of the Royal Society of London, Series B Biological Sciences, 163 (1965): 232-284 + pl. 6

Grainger, E., "On the age, growth, migration, reproductive potential and feeding habits of the Arctic char (Salvelinus alpinus) of Frobisher Bay, Baffin Island." Journal of the Fisheries Research Board of Canada, 10 (1953): 326-370 Johnson, Lionel, "The Arctic Char, Salvelinus alpinus." In Charr: Salmonid fishes of the Genus Salvelinus, edited by Eugene Balon, The Hague: Dr. Junk, 1980 Johnson, Lionel & Bonnie Burns (editors), Biology of the Arctic Charr: Proceedings of the International Symposium on Arctic Charr, Winnipeg: University of Manitoba Press, 1984 Jonasson, Petur (editor), "Ecology of oligotrphic, subarctic

Thingvallavatn." Oikos, 64(1/2) (1992): 1-439 Kawanabe, Hiroya, Fumio Yamazaki & David Noakes (editors), "Biology of Charrs and Masu Salmon: Proceedings of the International Symposium on Charrs and Masu Salmon." Physiology and Ecology Japan, special volume 1 (1989): 1-711

Klemetsen, Anders, Bror Jonsson & Malcolm Elliott (editors), "Proceedings of the Third International Charr Symposium." Nordic Journal of Freshwater Research, 71 (1995): 1-451 Machino, Yoichi & Nathalie Thibault, "Poissons & Bibliographies." In Faune & Flore du Grand Nord, edited by Nathalie Thibault, Paris: Grand Nord Grand Large, 1999 Nordeng, Hans, "On the biology of char (Salmo alpinus L.) in Salangen, north Norway." Nytt Magasin for Zoologi, 10 (1961): 67-123

Nyman, Lennart, "High, old and small: the dwarfs of

Chardom." ISACF Information Series, 4 (1987) 107-112 Savvaitova, Ksenia, Arkticheskie gol'tsy (Arctic chars), Moscow: Agropromizdat, 1989 (English translation in Canadian Translation of Fisheries and Aquatic Sciences, 5607 (1993): 1-245) Watson, Rupert, Salmon, Trout & Charr of the World,

Shrewsbury: Swan Hill Press, 1999 Yessipov, V., Materialy po biologii i promyslu Novozemel'skogo gol'tsa (Salvelinus alpinus L.) [Materials on the life history and fisheries of the char of Novaya Zemlya (Salvelinus alpinus L.)]. Trudy Arkticheskogo Instituta, 17 (1935): 5-71 (in Russian with English summary)

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