Documents released under a Freedom of Information request reveal excessive water use for irrigation, global warming and reduced snow packs are all taking a toll on trout stocks.
The details are in a confidential study conducted for the B.C. government.
Shuswap Environmental Action Society president Jim Cooperman says many of the affected lakes are public reservoirs being used for private irrigation by area ranchers.
He believes some ranchers don't have the right to use the water, but have been taking advantage of lakes and streams for years.
The study found small lakes in the Thompson region generate benefits estimated at $80-million annually, but combined environmental issues and human misuse are harming once-productive trout habitat. (CHNL)