Kootenai River White Sturgeon
The Kootenai River white sturgeon (Acipenser transmontanus) is a land-locked population of white sturgeon, a long-lived fish species, known to occur in western North America.
Kootenai River white sturgeon (Kootenai sturgeon) occur in Idaho, Montana, and British Columbia, Canada, and are restricted to approximately 167.7 River Miles (RM) of the Kootenai River extending from Kootenai Falls, Montana, located 31 RM below Libby Dam, Montana, downstream through Kootenay Lake to Corra Linn Dam at the outflow from Kootenay Lake in British Columbia.
The Kootenai River population of white sturgeon became isolated from other white sturgeon in the Columbia River baisin during the last glacial age (approximately 10,000 years ago).
Habitat fragmentation is the primary threat to Kootenai sturgeon. Construction of Libby Dam in Montana altered river flow patterns and reduced river productivity. Human development in the Kootenai basin resulted in a loss of ecological functions, and the dikes constructed along the river channel to prevent flooding eliminated sloughs, side-channels, and backwaters, which affected the ecosystem in multiple ways (e.g., reduction in riparian function and floodplain interaction). Excessive levels of pollutants in the 1950s and 1960s may have also reduced the long-lived fish’s ability to reproduce in the wild.