Fitch, L & Mee, J. (2026). Analysis of Selenium Tissue Concentrations in Multiple Fish Species of the Oldman River.

In brief, thirty-eight fish from five species (and representative of the fish assemblage of the Oldman River downstream of the Oldman dam) were analyzed for selenium concentrations in muscle tissue. The sample size of fish was small, yet the results provide warning signals of selenium impacts extending further down in the watershed from legacy coal mines.

Of the sportfish species (rainbow trout, brown trout, and mountain whitefish), 33 per cent of the fish exceeded Alberta’s threshold for the protection of aquatic life. This also has implications for people who consume these fish. Compared with fish in Alberta waterbodies not impacted by coal mining, the mean selenium species concentrations for Oldman River fish suggests a broader selenium problem for the Oldman ecosystem, both upstream and downstream of the Oldman dam.

The results of this reconnaissance study suggest a more systematic and comprehensive examination of selenium is urgently required to connect the dots between legacy coal mines and contamination of fish and aquatic invertebrates for the larger watershed.

For the complete report, click … here.