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<br />from a jet boat. It was next contacted from a jet boat in the Gunnison River at <br />RM 2.7 on 18 June and again at RM 1.4 by the land-based data logger on 19 June. <br />It was then contacted at the confluence of the Gunnison and Colorado rivers on <br />23 June. After that, this fish moved downstream and was contacted at the mouth <br />of Salt Creek in Ruby Canyon (RM 144.2). It was later contacted 15 July <br />downstream from Westwater Canyon at RM 109. It was last contacted at RM 112 on <br />21 July moving upstream. <br /> <br />The other transmitter-tagged pikeminnow was released at Pike's Bar (RM <br />178.8) 20 April. It was contacted four times from a jet boat and once from a <br />land-based data logger. It was not contacted until 23 June and had moved about <br />2 miles upstream and was still in the 15-mile reach of the Upper Colorado River. <br />It then moved downstream in the Colorado River and upstream in the Lower Gunnison <br />River as it was recorded by the data logger at RM 1.4 in the Lower Gunnison on <br />27 June. On 31 July it was located at Colorado River RM 162.2, immediately <br />downstream from Walter Walker State Wildlife Area. On 24 July it was contacted <br />at the head of Horsethief Canyon, RM 150.1, immediately downstream from the Lorna <br />boat landing. It then moved upstream and was last contacted 27 October near its <br />release point, RM 178.8. Both of these fish exhibited downstream movement prior <br />to and during the presumed spawning season. One fish, following spawning, then <br />returned upstream. <br /> <br />CONCLUSIONS <br /> <br />The following were conclusions from this evaluation: <br /> <br />1. No transmitter-tagged sub-adult or adult Colorado pikeminnow were <br />documented using the newly-constructed notch to pass by the GVIC <br />Diversion Dam. <br /> <br />2. Ten adult Colorado pikeminnow were captured upstream of the diversion <br />dam. It is unknown whether these fi sh had used the notch at the <br />diversion dam or simply passed over the diversion dam when it was <br />inundated during spring runoff in 1998 or during prior years. <br /> <br />3. A total of 2,505 fish was captured upstream of the diversion dam prior <br />to spring runoff (27 April) and during post-runoff (17 July to 21 <br />October). Of the 1,815 native and nonnative fish that were marked <br />downstream of the GVIC Diversion Dam, only one adult carp was <br />recaptured upstream of the diversion dam. This fish was assumed to <br />have used the drop structure and notch to pass by the diversion dam <br />because there was no water spilling over the diversion dam during the <br />one-week period between marking and recapture. <br /> <br />4. Forty-six fish were recaptured downstream of the GVIC Diversion Dam. <br />Forty were native fish and six nonnative fish. Recapture rate was <br />2.5% of all fish marked. <br /> <br />12 <br />