 Existing populations are in imminent danger from land-use activities and hybridization with introduced rainbow trout (resulting in cutbows) and Yellowstone cutthroat trout.Even the strongest populations in Glacier National Park and the Flathead Basin of Montana are in serious decline.Reasons for the critical condition of the subspecies include habitat destruction from logging, road building, grazing, mining, urban development, agriculture and dams, introduction of non-native hatchery strains, competition and hybridization from introduced non-native fish species.