Rybí restaurace Šupina a Šupinka, apartmány

Rainbow trout

Drawing © Radek Doško

  • Latin name: Oncorhynchus mykiss
  • Slovak: Pstruh dúhový
  • English: Rainbow trout
  • German: Regenbogenforelle
  • sort: Clupeiformes
  • family: Salmonidae
  • feed: omnivore, predator
  • life span:
  • sexual maturity: 2nd year
  • reproduction: October - January
  • common size: 25-40 cm
  • maximum: up to 120 cm

The area of the north Pacific stretching from California via British Columbia and Alaska to Kamchatka is the original habitat of this species.  Like of the brown trout, there is a number of strains (sea, lake, stream and other geographical strains) of which the sea migrating strain growing to the significant sizes, called steelhead in its home-country, is the best-known.   This strain is an attractive sport fish and it is rarer in most habitats than other strains of Pacific salmon. Only hundreds of specimens of this beautiful fish migrate to rivers to spawn.

Apart from that, the rainbow trout has been introduced to many places worldwide (Norway, Sweden, Argentina, Peru, Uganda, Kenya etc.) where wild forms can be found here and there.

The rainbow trout has been described several times because it is widely distributed and there is a huge amount of strains; the current scientific name has been used for a considerably short time, the rainbow trout can be found in older books under the Latin name Salmo gairdnerii.

Like the brown trout, even this species has been bred with the individual strains when hatching and pure original populations are rather rare nowadays.

It is not difficult to distinguish the rainbow trout from other salmonids.  Its body is grey or silvery with a strong horizontal pinkish band along the flanks.  The whole body is covered with small dark spots and, in contrast to other salmonids, there are lots of spots on the tail, dorsal fins and adipose fin, too.

Its body shape and colour vary widely and reflect the habitat, raising conditions and particular strain.  Both thin and monstrously stocky trout having just fragments of fins can be found.   The colour mainly varies in the overall intensity of colouring varying from silvery to completely dark.

The rainbow trout was first introduced to the Czech Republic from Germany in 1888. Later in the 20th century, it was introduced from Denmark and these specimens are said to have originated in Kamloops Lake in British Columbia (at that time called Salmo gairdnerii kamloops).

Breeding of the rainbow trout in pools, ponds and cages sunk into reservoirs is characterized by all features of modern large breeding farms including a huge number of stocks in a relatively cramped space and automatic feeding on granulated feeding mixtures.

The rainbow trout is being massively stocked to sport fisheries and   it spawns naturally in some rivers (e.g. Loučná, Metuje and a number of other rivers).  Unfortunately, as a result of excessive stocking of artificially bred specimens, rainbow trout having not fully developed fins and not behaving like wild fish can be often found and caught and fishermen often consider them “spotted roach”.   It is a pity and a result of the inability of our fishery corporation to separate sport fishing from fishing for food in some areas at least. Massive stocking of the rainbow trout arises from the inability to keep sufficient stocking rates of the original trout under the existing conditions and the efforts to satisfy the interest of fishermen.

You can find more information at www.mrk.cz Section ‘Fish Encyclopaedia’.