Life cycle


The brown trout spawns in the gravel at the bottom of streams in the period from September to November. The fingerlings hatch in the following spring and live in their native rivers for 2 to 5 years. The brown trout does not need swift rapids to reproduce the way the landlocked salmon does. It can reproduce in smaller, slower streams as well.

The fingerlings exit the river at the length of 18 to 25 centimetres. They school and migrate to lake areas to feed. The fish are called smolts at this stage. However, some fingerlings do not migrate, but remain in the river areas all their lives. These fish remain quite small.

The trout is more non migratory than its relative, the salmon. The majority of tagged fish migrate within one hundred kilometres of the place they were stocked. Unlike the landlocked salmon, brown trout swim upriver to the rapids to follow their prey and feed in the summer, too.

Once a trout has reached sexual maturity after two to five years in lake, it migrates back to its native river to reproduce. Many of the natural breeding grounds of the brown trout have been destroyed owing to water construction, but a few suitable breeding locations have survived.


taimenPhoto: A female brown trout caught for a brood fish at Lieksanjoki River











The project is co-financed by the LIFE+ -programme (EC)