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. RESULTS . . SUnmary Of Radiotagged Fish A total of 20 fish were caught by electrofishing and implanted w~th radio- transmitters during the first phase of this investigation, including 10 Colorado squawfish, 9 razorback suckers and one razorback sucker-flannelmouth sucker hybrid (Table 2). All fish, with the exception of one razorback sucker, appeared to be alive and behaving normally thoughout the study. The one razorback sucker (Carlin tag #06110), was found dead during the first radio tracking field trip, 1.2 miles downriver from its release site. Both the carcass and radio were deposited at the FWS/CRFP office in Vernal, utah. . A complete set of field data associated with the electrofishing effort to collect the 20 fish, as well as subsequent radiotracking information and habitat measurements have been submitted as a supplemental report to the BOR in Salt Lake City and the FWS/CRFP in Vernal utah. . Performance Of '1he Radiotelemetry Equipoent The frequency and pulse rate of each radiotransmitter were checked by FWS prior to transferring the tags to BIOjWEST. Also, the frequency and pulse rate were checked by BIOjWEST prior to and immediately after implantation (Table 3). Variation in frequency and/or pulse rate was detected in most of the radiotransmitters with decreases in pulse rate occurring most commonly. Generally, both the frequency and the pulse rates stabilized wi thin about a month after implantation, but some variation continued throughout the study and may be attributed to fluctuating cold water temperatures. . . Generally, the radio receivers provided by the FWS for this study performed satisfactorily. There was some initial difficulty distinguishing transmitters of very close frequencies and similar pulse rates. In one case, two of four fish aggregated in one area had such transmitters. As the study progressed, differences in transmissions from AVM and Smith-Root transmitters, which included differences in tone and duration of pulse, were more readily recognized. This aided in identifying transmitters. . Movement . Movement observed during this investigation was classified into three basic patterns, 'no movement', 'local movement' and 'transitory movement'. The no movement pattern was encountered frequently, especially with razorback suckers, and denotes little or no change in fish posi tioo during t'fi'e observation period. On several occasions, razorback suckers apparently remained in the same location for several weeks before moving either up or downriver. These fish were usually forced to move following observation periods, to assure the investigator of their fitness. . 13 .