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<br />been initially captured and PIT tagged downstream of the diversion dam either <br />sometime prior to- or during the 1998 runoff. Five of these eight fish were last <br />captured downstream of the diversion dam in 1998 between 23 April and 11 June, <br />one was captured in June 1997, one in April 1993, and one in June 1991. <br /> <br />This is not the first time that Colorado pikeminnow have been reported <br />upstream of the GVIC Diversion Dam. The U. S. Fish and Wildlife Service <br />(Osmundson and Kaeding 1989) documented a radio-tagged adult Colorado pikeminnow <br />moving upstream to the GVIC Diversion Dam in mid-July 1986. The fish eventually <br />passed the structure and moved upstream to the base of the Price-Stubb Dam. This <br />fish either moved upstream over the GVIC Diversion or could have passed around <br />the diversion dam via the Orchard Mesa Irrigation Diversion (OMID) bypass canal. <br />Flows at this time were approximately between 5,700 and 7,600 cfs over the GVIC <br />Diversion Dam, therefore it is suspected this fish may have passed around the <br />structure via the bypass canal. This fish remained until late-September when it <br />returned downstream and passed either over or around (via the OMID bypass canal <br />or through the GVIC flood gates) the diversion dam. The same fish returned to <br />the base of the GVIC Diversion Dam in late-July 1987 and progressed upstream to <br />the base of Price-Stubb Dam. It remained there until mid-September 1987, when <br />it again made its way downstream, passing the GVIC Diversion. <br /> <br />Valdez et al. (1982) sampled the Upper Colorado River between Palisade and <br />Debeque, Colorado (RM 210), between 1979-1981. Most of their sampling occurred <br />upstream of the Government Highline Diversion Dam but they did sample the river <br />reach between the GVIC Diversion and Price-Stubb dams once each during July 1979 <br />and April 1980. They reported collecting six native and four nonnative fish <br />species with electrofishing, fyke nets, gill nets, and seines. Valdez (1984) <br />sampled the Upper Colorado River between Government Highline Diversion and the <br />Price-Stubb dams with electrofishing, seines, dip nets, and drift nets between <br />April and September 1984. During the same period, he sampled the Upper Colorado <br />River between the Price-Stubb and GVIC Diversion dams, but only sparingly with <br />seines. Valdez did not collect any Colorado pikeminnow during these <br />investigations. Kidd (1982) caught sub-adult Colorado pikeminnow (number <br />unknown) in a backwater immediately downstream of the GVIC Diversion Dam in the <br />spring and early-summer of 1980. According to Kidd (personal communication), <br />this backwater is synonymous with the location of the present series of pools and <br />riffles that were constructed for fish passage in 1998 at the GVIC Diversion Dam. <br /> <br />Telemetry <br /> <br />Two adult Colorado pikeminnow were implanted with LOTEK@ transmitters in <br />mid-April, one approximately 2 miles downstream of the diversion dam and the <br />other approximately 4 miles downstream. However, neither these two or any other <br />pikeminnow that had active LOTEK@ transmitters associated with other ongoing <br />studies were detected moving through or downstream of the GVIC Diversion Dam by <br />the automated LOTEK@ data-logging station that had been deployed at the diversion <br />dam in early-April. <br /> <br />One pikeminnow that was captured and released at RM 183.0, 13 April, was <br />contacted first by a LOTEK@ land-based, automated data logger located on the <br />Gunnison River at RM 1.4. 14 June. It was contacted five times following release <br /> <br />11 <br />