Native Trout Restoration in the North Fork of the Blackfoot River: A Bite of the Big Apple

The North Fork of the Blackfoot River in western Montana is the site of developing large-scale (285km²) native trout conservation project. This area is entirely within the Scapegoat Wilderness upstream of the North Fork Falls.  Here, historical stocking introduced a minimum of 500,000 to 700,000 undifferentiated cutthroat trout including Yellowstone Cutthroat Trout (Oncorhynchus clarki bouvieri) and Rainbow Trout (O. mykiss) in lakes and streams.  The treatment area currently supports Oncorhynchus hybrids only, including introgressed native Westslope Cutthroat trout (O. C. lewisii). These fish are poorly suited to the high country as indicated by low population abundance and limited distribution.  If the restoration project proceeds, it will treat all fish-bearing water (about 72 km of an 137km perennial stream network) with rotenone over a three-year period, reintroduce drainage-specific Westslope Cutthroat Trout, and translocate native Bull Trout (Salvelinus confluentus) into the project area.  Though fisheries surveys have not detected Bull Trout upstream of the Falls, they are being considered for this project due to their ESA Threatened status and because current climate projections point to the loss of thermal habitat downstream of the North Fork Falls by 2040. If completed, this will be one the largest restoration projects of its kind in western North America.