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RESULTS AND DISCUSSION Radiotelemetry Six Colorado squawfish collected from upper Lake Powell near Gypsum Canyon were implanted with radio transmitters, between April 6 and May 28 (Table 1). One additional fish was implanted with an ultrasonic transmitter on April 6. Contact was lost with three fish, including the ultrasonic unit, as soon as the fish were released. However, the remaining four radio-equipped fish were periodically located over periods of time ranging from 5 days to 6 months after release, Three of these fish were followed downstream into the reservoir in April where contact was lost in deep water (Figure 9). Although one of these fish was never recontacted, the remaining two fish were recontacted in the Gypsum Canyon area in May and June. The fish that was relocated in June was again found in the Gypsum Canyon area at the end of July when radio tracking efforts were terminated in the upper reservoir. The most noteable movement was exhibited by the radiotelemetered fish that remained in the vicinity of Gypsum Canyon until early July. In mid-August this fish was found at RM 140, about 4 miles upstream from Black Rocks; an upstream movement of about 160 miles. In September the same fish was located near Clifton, Colorado, an additional 40 miles upstream. Four Colorado squawfish collected from the Gunnison River (1 fish), Colorado River (1 fish), and the region of the confluence of the two rivers (2 fish), were implanted with radio transmitters. Twelve additional Colorado squawfish collected from flooded gravel pits connected to the Colorado River; eight from Walker Wildlife area (RM 163.6), two from Island Backwater (RM 175.3), and two from Labor Camp (RM 183.2) were implanted with radios. Fish were implanted with radio tags and released between May 14 and June 18 (Table '2). Radio contact was maintained with most fish through August, and with some fish into October. Of the fish collected and tagged within gravel pits, nine were released inside the pits whereas three were released outside the pits in the river proper. Fish were released into the river because they were apparently leaving the pits when captured in trap nets. All fish released within gravel pits subsequently moved into the Colorado River. One of the fish released in Walter Walker Wildlife Area (WWWA) subsequently entered Connected Lakes pit for a short time while the fish was moving upstream. A Gunnison River fish apparently died sometimp after implantation; its movement is not reported herein. No long distance ( >50 miles) movements were observed for Colorado squawfish released in the Grand Junction area. However, total movement equaling about 40 miles was observed for some fish. In general, fish collected from WWWA (Figure 10) moved farther than did fish tagged in upstream areas (Figure 11). Most of the radio-equipped fish remained in the Grand Junction area during the study period; however, one Colorado squawfish released in the Gunnison River and four fish from WWWA moved to the Black Rocks region (RM 136) before contact was lost. Although ri4-