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185 `~TAT1JS OF I HE: FtJ17_ORBACK SLICKER XYRAU(.:HFN TEXAN(1S IN THE. COLORADO RIVER UPSTREAM FROM LAKE POWFL.L Charles W. NkAda U. ~. fish and Wildlife Service 529 25 1/2 Road, Suite Q-113 Grand Junction, CO 8150 the razorbhr_k Suc:k«~r Xyrauc:hen texanu~. is dist.ribut.ed throughout. the upper _ _.. rolorado River from upper I aka Pc~wF~l 1 +,o R i f la, ('Ci. Flowever, few specimen , have i~een cc, r r ee: i,ed i n recent years ono c.ne 5.pec r es i s cons i aerea rare. i he razorback sucker is listed as endangered by the state of Colorado and is protected by the state of Lltah, but it currently receives no federal protection. The Fish and Wildlife `~ervicc• (FW51 has collected 23 razorback suckers frorn the upper Colorado River ~:ince ]982. This number compares with 165 subadult. and adult Colorado squawfish F't~chocheilus luci_u_s and 300 adult humpback chub Gila cypha col~ler.t.ed during the same Lime period with equivalent effort. The lat.t.ar spFCies are 1~istNd as endangered by FWS. Colorado Uivision of Wildlife crews c:ollect.ed 7 ralorbac.k suckers in the Colorado River between 1979 and ].984 (personal communication, John Hawk-ins, Colorado State University). They estimated that 50 or more olorado squawfish were handled for every razorback collected. Une razorback sucker has been collected in the Gunnison River since 1980 (personal communication, P. Holden, 13iowestl. Razorback suckers are infrequently collected from thF Dirty Devil and Colorado River arms (personal communication, K. Lashmett, bureau of Reclamation) and San Juan River arm (personal communication, W. GuStaveson, Utah Division of Wildlife kesources) of upper take Powell. Current evidence indicates the razorback sucker i~, in a tenuous position in the upper (:olorado River. Of the four rare large-river fishas native to thr upper basin, only the bonytail G. elegans is less common. In addition, no evidence of successful recruit.rnent t_} the population h~.~s bean found in recant. yearti. ThP lack of r?cru i trr,,:~nt, indicates that th~> population wi i I continue t~~ decrease as individuals age and die. Adequate funds for research and management are needed to identify reasons for r.r,e rontinuin~ popu~lat.ion decline and tc~ reaverse the trend.