In Montana, a small stream that had been battered by mining and overtaken by non-native fish became the setting for a conservation effort that produced a striking recovery. White’s Creek, in the upper Missouri River basin, once supported only a tiny remnant population of native westslope cutthroat trout. After years of removing competing brook trout and rebuilding the damaged stream habitat, researchers recorded at least a sevenfold increase in the native fish population.
According to a 2002 study published in the Intermountain Journal of Sciences, the recovery of native westslope cutthroat trout in Montana’s White’s Creek demonstrated the importance of combining habitat restoration with the removal of non-native fish. The population had fallen to about 80 fish measuring at least 75 millimetres long in the early 1990s, partly because of competition with brook trout and damage caused by historic mining. Between 1993 and 2000, researchers repeatedly removed brook trout using electrofishing, while restoration work repaired a mining-damaged section of the creek and a fish barrier was installed to prevent the non-native fish from returning upstream.
