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<br />Fish Movement <br /> <br />Colorado squawfish moved throughout the study both locally and for longer distances in <br />the river. One fish moved approximately 7 miles upstream and then moved downstream <br />6 Yz miles by the end of the study. This particular fish moved upstream during a time <br />when flows were lowest in the summer and moved back downstream at higher flow rates. <br />The upstream movement occurred through numerous shallow riffles and either through or <br />around the Patrick Sweeney Diversion structure. <br /> <br />Other fish moved only slightly and stayed within the same river mile, however, on most <br />24 hour observations there was a local movement shown of several hundred feet by the <br />fish that were being observed with peak movement occurring after dusk. The activity <br />increased after dark with fish moving either upstream or downstream to a probable <br />feeding location and then returned to the original observation point. <br /> <br />Channel catfish and northern pike showed less movement during the study. Most of these <br />fish remained in the same river mile where they were originally captured with the <br />exception of two channel catfish that moved downstream approximately 4 miles at the <br />late October observation period. One of those was observed on the ground by ground <br />crews; the other was observed only from air and that contact was not verified on the <br />ground. <br /> <br />During one 24 hour observation of northern pike, that fish exhibited the same local <br />movement as Colorado squawfish. Activity increased after dusk. The fish moved <br />upstream several hundred feet. That movement peaked just before midnight and the fish <br />returned back to its original location before dawn the next day. <br /> <br />Habitat Use <br /> <br />Colorado squawfish almost exclusively used pools throughout the observation period <br />from July through October (Figure 36). Two of the five fish implanted did use run <br />habitat but only slightly during the entire eight weeks of observations conducted on the <br />river. In addition, one fish used an eddy pool, but less than 5% of the time of <br />observation. <br /> <br />Channel catfish used pools and runs but the majority of the time they were in pools <br />(Figure 37). The run habitat used was at a higher rate than that used by Colorado <br />squawfish and probably is indicative of difference in feeding behavior and general habitat <br />differences exhibited by the two species. <br /> <br />Northern pike, like Colorado squawfish, mainly used pools during the study. There was <br />some backwater habitat used by these fish. This was the only species that was observed <br />using the backwater habitat during the low flow period (Figure 38). <br /> <br />Yampa River Radio Telemetry Report <br />Miller Ecological Consultants, Inc. <br /> <br />Page 45 <br />January 23, 1997 <br />