Fish of deep and cold waters
During spring lake trouts move in surface levels, but when water starts to get warmer, lake trouts are going deep waters, even to 50-80 m. Cold water is necessary for lake trout.
Use of nutriments
Lake trout's main food is fish. It uses middle of the lake's schoolfishes like whitefish, vendace and smelt. When smaller it eats also crustaceans of the deep and after born plankton.
Spawning
Based on foreign, non-Finnish research, lake trout spawn between August and Novenber on rocky or gravel bottoms in 2-30 m deep. It is been caught big ready-to-spawn lake trouts from Lake Inari, but successful breeding remain unconfirmed.
Catch, size and records
Lake trout has a very long life as a fish, even 40-year-olds have been caught. It also grows slowly. For example in Lake Inari usual size of lake trout is 0,7-2 kg, but over fish over 7 kg weight has been caught.
Lake trout catch has been recently 10 tn at the best from Lake Inari.
In 1976 12 kg lake trout was caught from the sea area in front of Raahe.
Sources:- Koli, Lauri, Suomen kalat
- FGFRI's stats (In Finnish)
- Fish records (In Finnish)