Arctic Char, Bull Trout (lat. Salvelinus alpinus)
Reference work entry
Arctic Char, Bull Trout (lat. Salvelinus alpinus) – a migratory fish of the Salmonidae family. It has intraspecific forms which are different in external appearance, coloring, and way of life. The migratory AC has a tapering head of a conic form, the upper jaw is narrow and quite long with adult species, and the tail-stem is not high. The fish in the sea has a dark-green back with small spots, silvery sides, a white belly, and gray fins. The sides of the body sometimes have white or pink spots. In the river the coloring sometimes changes: the back gets olive-brown, the sides dark brown with silvery hue and numerous red spots, the belly gray and red, and the fins rose-red. In spawning period the fishes acquire special coloring: the body gets darker, the spots brighter, the male’s jaws become longer, and the lower jaw obtains an outgrowth while the upper obtains an indentation fit for the outgrowth. In this period the jaw edges, the belly, and pectoral, abdominal, and proctal fins are red or orange, and their external rays are milk-white. The maximum body length is up to 88 cm, usually 35–45 cm, and the weight sometimes reaches 15 kg. The fish is widespread in the North Atlantic, the Arctic, and North Pacific Ocean. The fish becomes mature at the age of 5–7 years old. It flows to the river in August of September. The spawning happens in autumn and winter in rivers and lakes. The fish lays eggs into nests on the rocky ground at the depth of 13–46 cm. The fertility is usually 3.5 thousand eggs. Precocious males take part in the process of spawning with migratory AC. Annually only a part of mature fishes lay eggs. The eggs are large (5 mm), light-yellow, or orange. Young fish leave their nests in spring and live in the river for 2–4 years. In the sea they fatten for several months close to the shored, feeding on fish. In rivers they fed on fish, shellfish, maggots of water, and flying insects. The AC is an important fish for industry and trade.
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