The bull trout (Salvelinus confluentus) is a threatened salmon species endemic to the Pacific Northwest. The fish evolved in the Columbia River Basin, and the Basin population is it's last major stronghold. Bull trout live in the Slocan River system.
Bull trout are freshwater char that spawn and rear in especially cold and clean headwater streams with low aquatic productivity. Spawning typically takes place in the fall. Spawning beds are often located in areas with substantial groundwater input, where upwelling groundwater creates cold water conditions.
Bull trout may move great distances within a river system. Studies have shown migrations of up to 350 km at this time, and wider ranging movement patterns may have been common prior to the extensive damming of the Columbia system. Like many other migratory salmon, mature bull trout return to their natal streams to breed.
Bull trout have extremely narrow habitat requirements, that is, they can only persist in a set of specific conditions. Their natural habitat is thus greatly restricted and fragmented. Bull trout populations are extremely vulnerable to watershed disturbances, including habitat alteration from dams, alterations in stream flow patterns, alteration in stream bed morphology and water dynamics, and alteration in temperatures.
Bull trout are an endangered species in much of their current range, and many sub-populations have undoubtedly been extirpated by development and land use change. The B.C. population is believe to be at risk due to the cumulative impacts of land use change and alterations to watersheds from forestry activity.
From: Bull Trout Streams of the Upper Columbia River Basin of Southeast British Columbia, James C. Bergdahl, 1996.