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<br />RM 21.6 (Freq. 40.7334) and 29.7 (Freq. 40.6233). <br /> <br />Considerable movement was observed among the five humpback chub implanted with <br />transmitters (Figure 8). Average distance moved weekly following the first three weeks of <br />August was 8.2 river miles per week. Greatest movement occurred prior to the third week of <br />August and coincided with greater declines in discharge. After discharge seemed to reach the <br />lower boundaries, movement distance between dates decreased (3.7 miles/week between August <br />22 and September 10). All humpback chub were observed to move upstream at some time during <br />the low flow period, indicating that all fish survived and moved during the length of the study. <br />By the end of October all fish were found in the river above river mile 24.2. <br /> <br />Following implantation of channel catfish minimal movement was detected until the last <br />aerial flight 29 October (Figure 9). Whereas, aerial locations of fish did not vary over one mile in <br />three of five fish (one fish moved 3 miles and one 2 miles), three of four fish moved more than <br />two miles between the last September and October aerial flight dates. One fish moved in <br />downstream in excess of20 miles and another moved upstream approximately 8 miles. <br /> <br />Discussion <br /> <br />Radio telemetry data from the post runoff period indicated that two Colorado squawfish <br />and all channel catfish, and all humpback chub remained in Yampa Canyon during the low flow <br />season. Humpback chub showed the greatest travel distance through this period followed by the <br />two Colorado squawfish and an apparent lack of movement by channel catfish, until movement <br />to overwinter sites within the canyon. Distance traveled between contacts for both Colorado <br />squawfish and humpback chub appeared to decrease following onset of baseflows. <br /> <br />The failure to obtain 24 hr movement data on humpback chub and Colorado squawfish <br />reduce the capability of defining available habitat in the canyon. Greater average depths and <br />increased quantity of large (boulder) substrate may have reduced the effectiveness of collecting <br />telemetry data. Increased trips (with monitoring rafts on each side of the canyon) and the use of a <br />new, longer whip antenna will be used to increase the efficiency of finding fish during the low <br />flo\\' period. <br /> <br />CHAPTER 2: HABITAT QUANTIFICATION <br /> <br />Methods <br /> <br />This study used the eight strata (river reaches) described by Miller ct al. (1 (82) for sample <br />site selection on the Yampa River (Table 1). Four strata were located below Cross Mountain and <br />three above Cross Mountain. Since strata 5 (Cross Mountain Canyon) and strata 7 (Juniper <br />Canyon) were short, they were not included in the sampling design. Sampling sites within the two <br />study strata were randomly selected by dividing the strata into 0.5 mile segments, named clusters. <br /> <br />14 <br />