Brook Trout is the major sport fish in the canyon. It is exotic and more tolerant of metals than rainbow, cutthroat, and brown trout, but not a native species to Colorado. The biggest challenge to stream life is from toxic heavy metals leaching from upstream mine sources. Due to high toxicity and competition with the Brook Trout, the Greenback Cutthroat Trout, native to this area, has almost entirely disappeared in Colorado.
While the Brook Trout remains a favorite sport fish, it is not recommended that anglers eat fish taken from the Canyon due to high toxicity.