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were contacted over 400 days. One fish (.150 Mhz) was never contacted following release. Only nine radio contacts were made with three different fish during 1995. Following release, fish either remained at the stocking site or dispersed downstream. Throughout the study, fish collectively moved a total of 481.5 river miles, most of which was predominantly downstream (385.6 miles; Figure 2). The mean maximum displacement for the 20 fish was four times greater downstream than upstream (19.3 versus 4.8 miles: Figure 3). Eight fish exhibited both up- and downstream movement sometime during the contact period: only three fish (.010, .050, and .241 Mhz) exhibited greater upstream than downstream movement. Eleven fish exhibited only downstream movement. Of particular interest was the movement of one razorback sucker (.260 Mhz). This fish was released at RM 211.1 and passed over the Government Hi ghline Diversion and Price Stubb dams, and the Grand Valley Irrigation Diversion. It was contacted on 24 and 27 June 1994 in "Hotspot Pond" at RM 174. It was last contacted downstream at RM 170.6 8 August 1994. Although two other fish (.300 and .620 Mhz) also passed over these three dams, it is uncertain whether they were alive at the time. Radiotag .300 Mhz was later recovered at RM 162.3, 9 August 1994 and the disposition of radiotag .620 Mhz is unknown since its last contact 15 June 1994 at RM 168.3. Fish .050 Mhz exhibited the greatest upstream movement. This fish moved 36.4 miles upstream and the last contact was 11.2 miles upstream from where it was stocked. Fish .010, .050, and .241 Mhz were the only three fish that were determined to be alive at last contact. These three fish had all moved upstream from their former radio contact locations. Radio contact had been lost with these three fish for several weeks during runoff in 1995. These fish may have migrated to reaches upstream in the Upper Colorado River that were not searched during this time and returned downstream later following runoff, or, their radio signal was not detected by radio tracking crews duriro runoff. The movements of these three fish were unlike the 17 other stocked razo-back sucker. All three of these fish initially moved downstream, eventually returned to their release sites, and then moved upstream from their release sites. At the termination of the study, 3 fish were confirmed alive, 10 were missing, 2 were confirmed dead, and 5 were presumed dead. Four radiotags were recovered, the first on 12 May, the last on 25 August 1994. Mortality in 1994 did not appear to be immediate but delayed following stocking. The low number of radio contacts in 1995 suggests either radiotag failure or missing fish had moved outside the tracking search routes. In any event, post-stocking survival was low. Confirmed mortality was 10%. Actual mortality was likely as high as 85% if missing and presumed dead fish were included. Gunnison River A total of 195 individual radio contacts was made periodically with 23 of the 25 fish released. Between 12 April 1994 and 1 November 1995, radio contact was made with fish on 47 different days. Radio contact ranged from 29 to 532 days (Table 2). Eleven fish were contacted between 113 and 146 days; only one fish was contacted over 150 days (.683 Mhz). Two fish (.112 and .320 Mhz) were never contacted following release. Of the thirteen radio contacts during 1995, 8