Salmo trutta fario
| Brown trout | |
|---|---|
 | |
| Scientific classification | |
| Order: | Salmoniformes |
| Family: | Salmonidae |
| Genus: | Salmo |
| Species: | Salmo trutta |
| Binomial name | |
| Salmo trutta fario Linnaeus, 1758 | |
The brown trout (Salmo trutta fario), sometimes also river trout,[1] is a predatory fish of the Salmonidae family and a subspecies or morph of the trout species, Salmo trutta, which also includes sea trout (Salmo trutta trutta) and a lacustrine trout (Salmo trutta lacustris). Depending on the supply of food, brown trout measure 20 to 80 centimetres in length; exceptionally they may be up to 1 metre long and weigh up to over 13 kilogrammes. Their back is olive-dark brown and silvery blue, red spots with light edges occur towards the belly, the belly itself is whitish yellow. The brown trout usually attains a weight of up to 2 kilogrammes. They can live for up to 18 years.
Habitat
Brown trout live in fast flowing, oxygen-rich, cool clear waters with gravel or sandy riverbeds. They occur across almost all of Europe, from Portugal to the Volga, with the exception of Central Anatolia and the Caucasus regions. They are found as far north as Lapland. They do not occur in Greece or on the islands of Corsica, Sardinia and Sicily.
Brown trout are very faithful to their habitat (i.e. they live only at one spot and do not migrate), leaving it only to reproduce. Even after being disturbed they will return to their traditional sites. The adult brown trout requires its own territory. During the day it is hidden in the shadows of the river bank, facing upstream.
Depending on size and habitat, they feed mainly on insects and insect larvae that live in water, small fish such as bullheard, small crustaceans, snails and other water animals. Cannabalism has also been frequently observed among brown trout. They are fast swimming predators, but in rivers and streams they will usually take prey that is being driven past by the current.
Reproduction
Brown trout spawn between October and January. The fish fan through rapid movements of the tail stock and caudal fin a shallow pit in the rock riverbed, into which about 1,000 to 1,500 reddish, four to five millimetre wide eggs are laid in several pits. The fish larvae emerge after two to four months.
The brown trout has a special significances as a host fish for the glochidia of the freshwater pearl mussel.
Other forms
Because trout live in habitats with fixed boundaries, in addition to the brown trout, Salmo trutta fario, there are various other subspecies of Salmo trutta. See Species of Trout.
Humankind and brown trout
In the past, European waterbodies were heavily and artificially stocked with rainbow trout, a native of America that grows more quickly and is less demanding of water quality. It is disputed whether this threatens the brown trout. Today, it is bred in fishponds with almost the same rate of success as the rainbow trout, for food and for restocking rivers. To protect native species of fish, the stocking of rivers with non-native species has been restricted for several years.
Brown trout makes an excellent fish dish.
Brown trout is very popular with anglers. It is frequently fished using artificial lures. Angling with natural lures (worms, maggots, grasshoppers) is discouraged in most rivers because it is difficult to throw those trout back that are below the minimum landing size uninjured, when they have ingested this food so quickly and deeply.
Hybrids
The tiger trout (Salmo trutta fario × Salvelinus fontinalis) is a genetic cross between a brown trout and a brook trout. It gets its name from its characteristic golden yellow markings. Tiger trout are sterile, despite male and female may be distinguished by their external markings. The female tiger trout does not develop any gonads. By contrast, male tiger trout develop testicles as well as secondary sex features such as kypes, humps, darker and thicker skin and a lighter fillet colouring during the spawning season.
Angling
Fly rods are used to catch brown trout. Medium-sized, wet and dry flies are thrown into streams with a rod of AFTMA Class 4-6 and are intended to mimic an emerging or egg-laying insect. A spinning rod can also be used in some waters. For this purpose, a light spinning rod and various artificial lures, such as spoon lures and spinners are used. In using wobblers and rubber fish care should be taken because they are banned on some waterbodies or may only be used with restrictions.
References
- ↑ John Gunn, editor (2004), Encyclopedia of Caves and Karst Science, New York/London: Taylor & Francis, p. 1278. ISBN 1-57958-399-7.
Literature
- Fritz Terofal: Süsswasserfische in europäischen Gewässern. Mit 200 farbigen Darstellungen von Fritz Wendler. Mosaik Verlag u. a., München u. a. 1984, ISBN 3-570-01274-3.
- Alexander Kölbing, Kurt Seifert: So macht Angeln Spass. Mehr wissen – mehr fangen. 5., durchgesehene Auflage. BLV, München u. a. 1995, ISBN 3-405-13746-2.
- Roland Gerstmeier, Thomas Romig: Die Süßwasserfische Europas. Für Naturfreunde und Angler. Kosmos, Stuttgart 1998, ISBN 3-440-07068-9.
External links
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Look up Bachforelle or River trout in Wiktionary, the free dictionary. |
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