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3 (i ) ,Wv i i iii (vu. ~ ~ ~ ailu ~) i7iuVru uN~ i,r'edm i i1 ti"i~ ureeri R"i ver 7 rom i.iie initial release site reaching the upstream limit of movement in late June-early July after travelling about 80 km. These two fish then moved back. downstream past the point of release. Fish No. 2 was last located by airplane in Labyrinth Canyon, over 300 km downstream from its release point. Fish No. 3 ascended the White River to a point 56 km above its mouth, returning to the Green River-White River junction; (2) the re- maining two. Colorado squawfish (No.'s 4 and 5) were relatively stationary. Fish No. 4 remained within 5 km of its release point. Fish No. 5 did not travel further than i6 km from its release point. We recaptured one Colorado squawfish from each group exhibiting the two different movement patterns to determine if there was any relation- ship between these patterns and sex, sexual maturity, condition of the fish or effects of carrying the implanted radio transmitter. Fish No. 4 (stationary group) was recaptured and dissected August 8. This fish was an immature male. Fish No. 3 (movement group} was recaptured and dissected September 2. This fish was a,female..in..an advanced stage of sexual maturity. While monitoring the movement of Fish No. 3 it was observed orienting to a riffle area in the Green River July 2 and orienting to another riffle area in the White River July i6 (after a movement of about 161 km in 5 days). The significance of this behavior is unknown. However, the data indicate considerable movement during the expected spawning season by mature fish in contrast to little move- ment by immature fish. An inspection of the viscera of_the two recaptured Colorado squaw- fish indicated no obvious adverse-effects from the implanted fish .module.. The fish module was effectively walled off from the intestines by ad- hesions and had to be teased free from this"mass for inspection. No evidence of irritation to internal organs was seen in either fish. The small size of the fish module and the absence of any sharp projections was no doubt responsible for this desired condition. The implanted razorback sucker (fish No. 7, Table 1) moved about 6 km downstream of its capture location and into the Duchesne River. It remained less ,than 1 km inside the Duchesne until flooding occurred in early June when it moved into the Green at the mixing zone of the two rivers. The sucker ..then slowly moved upstream in the Green River about 11 km. Contact was lost at that location-August 13. Attempts to recap- ture this fish were unsuccessful. At times we experienced difficulty re-establishing contact with some of the fish. There are two explanations for this problem. In the case of fish No. 6 (Table 1), the largest Colorado squawfish, we believe that its radiotransmitter ceased to work. For other fishes it appears that high conductivities (Table 2) combined with depths of over 2 m limited our ability to locate fish. Fortunately the area of the Green River we studied had few depths of over 2 m. Water conductivity in the Green River was lowest (Table 2) in June (x=202, n=9) and highest in September (x=809, n=6). Conductivity in the Duchesne River was recorded at 1950,ymho on April 18.