Brook trout
Boulder Mountain is routinely held in high regard by Utahan's as a fisherman's paradise. Fishing opportunities began on the mountain in the 1950s when juvenile fish(fry) were carried via horseback and planted in the area's high alpine lakes and streams. Brook trout are the prominent species stocked on Boulder Mountain. Colorado River Cutthroat are the fish species native to the area. In 2014, a committee consisting of anglers and local residents convened to determine the future management of the fisheries on Boulder Mountain. This committee assisted the Utah Division of Wildlife Resources in resolving the issue of overpopulating brook trout in the alpine lakes of Boulder Mountain. Based on the discussion, 35 percent of the lakes would be managed for trophy brook trout. The management plan categorized each of lakes into ten different sections: North Creek, North Slope, South Slope, East Slope, West Slope, Boulder Top, Griffin Top, and Escalante Mountain. The management plan introduces splake, tiger, and cutthroat trout to the waters that the committee deemed appropriate. Colorado cutthroat populations have steadily decreased since the introduction of brook trout to the area. Emphasizing the importance to re-establish a healthy population of native trout to the area sterile brook trout (triploid), along with other sterile trout species, such as tiger and splake trout, were introduced to increase fishing opportunities.