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RESULTS AND DISCUSSION Movement and Migration Radiotelemetry A total of 14 adult Colorado squawfish were implanted with radio- transmi tters in the DNM and the upper Yampa Ri ver in 1983 (Table 1). Tracking of these fish was successful and contact was maintained with most of the fish. Even so, adverse flood conditions made it difficult to locate and follow fish, and contact was lost with 6 fish, including 5 in the Yampa River during the spawning season (July-August). Eight fish implanted in the Yampa and upper Green migrated to the lower 32 km (20 mil, of the Yampa Canyon and spawned there. The migration observed in 1983 (Figure 2) was almost identical to the pattern observed by FWS in 1982 and 1983 (Figure 3). The movement of 18 Colorado squawfish, radiotracked to the Yampa spawning grounds in 1981, and 1983 ;s presented in Table 2. The results of radiotracking during the 1981-83 spawning seasons were very similar to those obtained by the NPS-CDOW study in 1982 (Wick et al. 1983). The distance moved by the 18 Colorado squawfish in reaching the spawni ng grounds (Table 1) vari ed from 12 to 216 km (7 to 134 mil and averaged 99 km (62 mil. In 1981 and 1983, fish radiotagged in the Green River moved into the same spawning grounds used by the fish from the upper Yampa River. During spring electrofishing efforts for adult Colorado squawfish, two Colorado squawfish that had been implanted with radiotransmitter during the 1982 NPS Study (Wick et al. 1983) were recaptured. Fish No. 1166 was originally tagged at RK 27 on July 1981. It was recaptured by NPS/CDOW personnel at RK 85 on 25 March 1982 and implanted with a radio- transmitter. It was recaptured at RK 85 on 5 May 1983 and implanted with another transmitter module. This fish migrated to the lower Yampa Canyon and was found in association with other spawning Colorado squawfish (Table 2). It then returned to RK 86 (RM 53.8) on about 18 August. The other fish, No. 3284, was captured by NPS/CDOW personnel at RK 170 (RM 105) on 13 April 1982 and implanted with a transmitter. We recaptured this fish at RK 25 (RM 11) on 9 May 1983 and implanted another transmitter. Although we lost contact with No. 3284 after June 7, it was relocated at RK 145 (RM 90.6)on August 19. Contact with these two fish in 1982 was lost before any migratory patterns could be established, but some IImigratory tendencies" were noted (WiCk etal 1983). Collections-Recaptures There have been 18 tag returns on Colorado squawfish tagged or recaptured by"FWS in the Yampa River from 1981-1983. Of these, one fish (1166) discussed above has been captured three times (Table 3), and implanted with a radiotransmitter twice. Of the 18 Colorado squawfish recaptured, 15 recaptures were made after the fish had been tagged for a year, three after 2 years and two after 3 years (Table 3). Two. tag returns came from anglers, or 11% of the Colorado squawfish taken 6