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willow 13,200 feet. Due to a lack of suitable habitat and limited species range, OSM has <br />determined that the TR-120 will "not effect" the continued existence of the Uncompahgre <br />fritillary butterfly. <br />Colorado pikeminnow <br />The Colorado pikeminnow (Ptychocheilus Lucius) is a torpedo-shaped fish with an olive-green <br />and gold back, silver sides and white belly. The Colorado pikeminnow thrives in swift flowing <br />muddy rivers with quiet, warm backwaters and are primarily piscivorous, but smaller individuals <br />also eat insects and other invertebrates. These fish spawn between late June and early September <br />and when they are 5 to 6 years old and at least 16 inches long. Spawning occurs over riffle areas <br />with gravel or cobble substrate. The eggs are randomly splayed onto the bottom, and usually <br />hatch in less than one week. <br />Humpback Chub <br />The humpback chub (Gila cypha) is a streamlined minnow with a concave skull and a prominent <br />nuchal hump at the occiput, the back end of head marked by a line separating scaleless and scaled <br />portions of epidermis with a caudal peduncle thin but not long snout that overhangs upper lip and <br />scales often minute or absent on keel. Adults are dark on top and light below and fins rarely have <br />yellow-orange pigment near base. Adults are usually range from 12-16 inches long and weigh 3/4 <br />to 2 pounds. The humpback chub historically ranged in the mainstem Colorado River preferring <br />slower eddies and pools downstream to below the Hoover Dam site, however, present <br />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 and like most suckers 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. Fins are dusky with yellow pigment near base, <br />prefering eddies and pools, not swift currents. The bonytail has a concave skull arching into a <br />nuchal hump predorsally with a long and slender snout that does not overhang the upper lip. <br />Scales often minute or absent from chest, stomach. Adults of seven years of age can be 14 inches <br />long and weigh more than one pound. Found historically throughout the Colorado River <br />Drainage however, in recent years bonytail have only been taken from the Green River in Utah <br />and lakes Havasu and Mohave.