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River preferring slower eddies and pools downstream to below the Hoover Dam site. However, <br />present populations are restricted to areas in, and upstream of the Grand Canyon. <br />Razorback Sucker <br />The razorback sucker (Xyrauchen texanus is brownish-green with a yellow to white-colored <br />belly and has an abrupt, bony hump on its back shaped like an upside-down boat keel. Razorback <br />suckers are found in deep, clear to turbid waters of large rivers and some reservoirs over mud, <br />sand or gravel. Like most suckers it feeds on both plant and animal matter. Razorback suckers <br />can spawn as early as age 3 or 4, when they are 14 or more inches long. Breeding males turn <br />black up to the lateral line, with brilliant orange extending across the belly. Depending on water <br />temperature, spawning can take place as early as November or as late as June. In the upper <br />Colorado River basin, razorbacks typically spawn between mid-April and mid-June. <br />Bonytail <br />The bonytail (Gila elegans) is a highly streamlined fish, dark on top, light below, often very dark <br />in clear waters and pale in turbid waters. The fins are dusky with yellow pigment near the base. <br />The bonytail prefers eddies and pools, not swift currents. The bonytail has a concave skull <br />arching into a nuchal hump predorsally with a long and slender snout that does not overhang the <br />upper lip. Scales are often minute or absent from the chest and stomach. Adults seven years of <br />age can be 14 inches long and weigh more than one pound. The bonytail was historically found <br />throughout the Colorado River Drainage. However, in recent years bonytail have only been <br />taken from the Green River in Utah and Havasu and Mohave Lakes. <br />The USF&WS has previously determined that water depletions in the Upper Colorado River <br />System are a major source of impact to the endangered fish species. Continued water <br />withdrawals have restricted the ability of the Colorado River system to produce the flow <br />conditions required by the various life stages of these fish. <br />As a part of its permit application Sage Creek Coal Company, LLC provided a water balance for <br />the proposed mine based on an estimated production rate of 2.0 million tons per year. <br />Accounting for noncontributory mine inflows, surface dust controls, and evaporative losses from <br />drainage controls Sage Creek Coal Company, LLC estimates that its water depletion for the <br />proposed mine will be 4.6 ac/ft per year. <br />Based upon this information, OSM has determined that the proposed Sage Creek Mine "may <br />effect, and is likely to adversely effect" the continued existence of the Colorado River Fishes. <br />Greenback cutthroat trout <br />The greenback cutthroat trout (Oncorhynchus clarki stomias) is a member of the Salmonidae <br />family, and is a subspecies of O. clarki. The subspecies feeds on aquatic insects as well as <br />terrestrial invertebrates. <br />4