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<br />pi kemi nnow , radiotagged in both 1996 and 1997, were contacted <br />in the Colorado River from river mile 134 to 170. <br /> <br />In 1998. two of the three pikeminnow that had been <br />radiotagged in May and June. translocated upstream of the <br />Redlands Diversion Dam. moved downstream over the diversion <br />dam and into the Colorado River. returned in early-August to <br />the Gunnison River. These fish ultimately were both located <br />in the plunge pool of the Redlands Diversion Dam plunge pool <br />on 8 August. They both remained here for 20 days. The <br />return movement of these two fish to the Redlands Diversion <br />Dam plunge pool in the lower Gunnison River from the Colorado <br />River following the spawning period was similar to the return <br />movement of four radiotagged pikeminnow in 1996 and two <br />radiotagged pikeminnow in 1997 to the same plunge pool in the <br />lower Gunnison River. <br /> <br />5. The mean length of fish that used the fish passageway in 1997 <br />(534 mm) and 1998 (516 mm) were significantly smaller (Figure <br />2) than those captured and selected for radiotag implantation <br />(1996: 733 mm; 1997: 688 mm: 1998: 691 mm). <br /> <br />VII. Recommendations: <br /> <br />A. Continue to collect movement data from land-based tracking <br />stations and from boat tracking on adult Colorado pikeminnow <br />radiotagged in 1998 during the fall of 1998 and winter and spring <br />of 1999. <br /> <br />B. Radiotag up to 10 Colorado pikeminnow of similar length (450-550 <br />mm) that have been collected in the fish trap during 1997 and <br />1998. This will require using a smaller radiotag than was used <br />in 1996, 1997, and 1998. A manufacturer has been contacted to <br />determine if a smaller radiotag than that used in the past three <br />years with a comparable life expectancy (360-days) can be <br />fabricated and implanted in the size of pikeminnow (e.g.. >800 <br />grams body weight) that have used the fish ladder in 1997 and <br />1998. Colorado pikeminnow collected from the fish trap would be <br />used. However. pikeminnow from the lower Gunnison 'River that are <br />of similar length to those in the fish trap could also be used. <br /> <br />C. Commence operation of the fishway in late.March or early-April <br />1999 and continue through October. Continue to monitor the <br />species and number of fish collected in the fish trap during <br />1998. Compare results with 1996. 1997. and 1998. <br /> <br />CAP-4B.6 <br />