Snake River Finespotted Cutthroat Trout
The watershed that drains the headwaters of the Snake River is unusual in that it has two genetically pure forms of native cutthroat (Oncorhynchus clarkii): the “large-spotted,” or Yellowstone, cutthroat trout (YCT) and the Snake River “fine-spotted” cutthroat trout (SCT), which has a much smaller native range entirely within the Snake River basin. Fish stocking and natural hybridization have resulted in intermediate forms of cutthroat trout, but the large-spotted and fine-spotted forms appear to have maintained distinct populations through reproductive isolation in parts of the Snake River drainage. In 2006, the USFWS determined that listing of Yellowstone cutthroat trout (both YCT and SCT) as threatened or endangered was not warranted. The SCT has not been formally recognized as a different subspecies from the YCT (O. c. bouvieri) and its status remains unresolved.