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198=! Co~lect ion o~ ~~i s,. From the ~_ _ ~ : D~~-_il r,:: of Lake ?Dwell ``-:r h '.i:;Just 1°84 fish were sampled from the e::tre~~~e upper F_-or; January ~. nub , ;portions of the Dirty Devil Arm of Lake Powell. The original objective of the study was to capture razorback suckers, surgically implant them with radio tags and track the fish to potential spawning areas. k'e were especially interested in finding out the significance of the Dirty Devil River to the life history of the razorback, in particular spawning. As summarized in Table I, seven adult razorbacks were captured. Of these, five were implanted with the tags. unfortunately, it was discovered that the relatively high salt concentrations in the water interfered with the effective transmission of the radio signal. Short-life sonic tags were tested and were found to be effective, however; longer duration tags were not available until after razorbacks were no longer being sampled. The initial capture of Colorado squawfish in March was unexpected. As were the razorbacks, these fish were marked with an external Carlin tag, and three of the fish were implanted with radio tags. One of these tagged fish was released several miles away in the Colorado Arm of Lake Powell near Rockfall Canyon. None of these fish were relocated by radio receiver although one was recaptured by netting approximately two weeks later. As Table II indicates, several of the squawfish were recaptued up to three months after the initial capture, inferring little seasonal movement. Although, one squawfish was captured in the Dirty Devil Arm two months after being caught and tagged in the Colorado Arm, about 50 river miles away. After June, neither fish species was collected and similarly fewer gamefish were taken. One probable explanation is these species were avoiding the extreme warm water temperatures of the shallower water, seeking out cooler water in deeper portions of the reservoir.