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In formulating this opinion, the Service considered adverse and beneficial effects likely <br />to result from cumulative effects of future State and private activities that are reasonably <br />certain to occur within the Project area, along with the direct and indirect effects of the <br />Project and impacts from actions that are part of the environmental baseline <br />(50 CFR 402.02 and 402.14 (g)(3)). <br />Status of the Species in the Action Area <br />The action area includes critical habitat for Colorado pikeminnow and razorback sucker <br />on the Colorado River from Salt Creek downstream to Lake Powell. Several segments of <br />the Colorado River in Ruby Canyon (Black Rocks) and Westwater Canyon are critical <br />habitat for humpback chub and bonytail. Estimates of wild adult Colorado pikeminnow <br />in the upper Colorado River (from Palisade, Colorado to Lake Powell) were <br />approximately 780 fish in 2003. This population estimate includes the 15-mile reach of <br />the Colorado River above the confluence with the Gunnison River, whereas the action <br />area does not include the 15-mile reach. However, fish can freely swim into this reach <br />from the Colorado River below the confluence with Salt Creek, so the upper Colorado <br />River is considered one population. Few wild razorback suckers occur in the action area; <br />however, the population is being augmented by stocking both in the Colorado and <br />Gunnison Rivers. Humpback chub occur in Black Rocks, Westwater Canyon, and <br />Cataract Canyon, but not in other river reaches in the action area. Wild bonytail are <br />extremely rare in the action area, but an active stocking program is augmenting the <br />population. <br />FACTORS AFFECTING THE SPECIES ENVIRONMENT WITHIN THE ACTION <br />AREA <br />CRITICAL HABITAT - COLORADO RIVER FROM GUNNISON RIVER CONFLUENCE TO LAKE <br />POWELL <br />Historically, the Colorado River produced high spring turbid flows that maintained <br />critical habitat by inundating floodplains, maintaining side channels, and creating <br />backwaters. The Colorado River below the confluence with the Gunnison River flows <br />approximately 18 miles through the Grand Valley. In the Grand Valley reach, numerous <br />gravel pit ponds occupy the floodplain and many of the river banks have been armored <br />with riprap. The river channel is braided around vegetated gravel islands and the habitat <br />consists of runs, riffles, eddies, backwaters, and side channels. <br />The Colorado River downstream of the Grand Valley flows through 29 miles of <br />Horsethief and Ruby Canyons with limited floodplain areas and shear sandstone walls. <br />Black Rocks is a mile-long reach of river that flows through a geologic upthrust of <br />metamorphic gneiss that confines the river creating a deep channel with strong eddies and <br />turbulent currents. Five miles downstream, the river flows through Westwater Canyon <br />for 14 miles. Westwater Canyon also is formed by an upthrust of black rock that creates <br />unique habitat conditions similar to Black Rocks but with significant whitewater rapids. <br />This reach encompasses critical habitat for humpback chub and bonytail from upstream <br />of Black Rocks to below Westwater Canyon. <br />28