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Fish were successfully located and monitored in the upper study reach of the river, however, site locations of fish in Yampa Canyon were unsuccessful and no 24 hr monitoring was accomplished. Telemetry data results from Yampa Canyon are provided in this report and the results from fish in the upper study reach are located in the companion report (Miller and Rees 1997). Results Two trips were made through Yampa Canyon to implant radio transmitters in the four target species and two additional trips were made to monitor specific locations of transmitter implanted fishes. Sampling trips were made 1-5 July, and 15-19 July to implant study fish and monitoring trips were made 3-6 September, and 30 September through 5 October, 1996. During the first collection trip 5 Colorado squawfish (RM 23.8), 4 humpback chub (RM 37.5, 23.8, 18.2, and 16.8),3 channel catfish (RM 36.0, 18.2, and 16.8) and no northern pike were implanted (Appendix 1, Table 1). During the second collection trip 1 humpback (RM 36.2) and two channel catfish (RM 39.5 and 37.3) were collected. During the first collection trip all five Colorado squawfish and one humpback chub were collected at Big Joe Rapid (RM 23.8). A large spawning aggregation of roundtail chub were observed at this location, and the single humpback chub collected showed spawning coloration. During the two telemetry monitoring trips only two ground contacts were made, a Colorado squawfish (frequency 40.6332 at RM 10.3) and a channel catfish (frequency 40.5739 as RM 18.2), both during the 3-6 September trip. Site inspection of the Colorado squawfish contact indicated no movement of the signal. Therefore, either the fish shed the transmitter or died following implantation. No ground contact was made from any humpback chub in either monitoring trip. In an effort to increase the efficiency of finding fish in Yampa Canyon, a large 18' whip antenna was used during the second monitoring trip, however. no fish contact was made. Despite the lack of ground contacts, movement patterns of Colorado squawfish, humpback chub and channel catilsh were observed from aerial surveys. Among the Colorado squawfish implanted, two left Yampa Canyon during the second week of August one month following implantation. One fish either died or lost its transmitter and t'vvo fish remained in Yampa Canyon through the low now period until at least 29 October 96. All humpback chub and channel catfish implanted in Yampa Canyon remained in the Canyon through the last aerial f1ight in 29 October. Of the two Colorado squawfish that remained in Yampa Canyon, one remained in the upper reach of the canyon and the other in the mid to lower reach of the canyon. Both fish appeared to remain in a general area of the river following 15 August (Figure 7). Following mid August, one fish ranged from RM 12.1 to 20.1 (Freq. 40.7334), and the other (Freq. 40. 6233) from 39.1 to 43.3 between mid August and late September. On 29 October those same two fish were found at 12