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(1998-1999), and Desolation (2001) canyons, which yielded no stocked bonytails. One stocked adult bonytail (TL 370 mm) marked with a CWT was captured in Gray Canyon (RM 148) during the 2002 humpback chub population estimate. Distribution of other Gila species Figure 14 illustrates the distribution of other Gila species in relation to release sites for the Colorado and Green rivers. The vast majority (87%) of other Gila found in the Colorado River were concentrated near the Dolores River (RM 90-100). In the Colorado River, other Gila species tended to increase in size as you moved downstream from the Dolores River. In the Green River, other Gila species were found more frequently in Gray Canyon (RM 132-140) and within an area 20 river miles below the stocking site. Overall abundance in both rivers appears to be relatively low with only 197 being captured in six years of sampling the Colorado River and 104 captured in five years of sampling the Green River. Adult BonytaU Telemetry Overall, survival of radio-tagged bonytail was excellent throughout the study. Only one of the 49 bonytail implanted was suspected to be deceased before tag failure. Survival of the bonytail was confirmed via daily movements throughout the life of the tags or until the fish had moved out of monitored areas. This was a vast improvement over the confrrmed mortality rate of 74.4% experienced by Chart and Cranney (1993) during the tracking of 86 bonytail in 1988 and 1989. The most important variable affecting survivorship of radio-tagged fish was likely age at release. Other possible factors include, the number of handling occurrences, and location of surgery and recuperation. In 1988-89, the seven and eight year old bonytail implanted by Chart and Cranney (1993) were transported from Dexter National Fish hatchery to Vernal, Utah, and placed in holding pens, and then transported by truck to Ouray National Wildlife Refuge where they were held until the date of their release. On the date of radio implantation, they were transported by truck to the stocking sites for bank side surgery. Tagged bonytail were then either immediately released, held in pens in the river, or returned to the circular tanks at Ouray National Wildlife Refuge for later release. In contrast, the bonytail implanted in 1997-2000 were one to four years old, and they were implanted with radio tags and allowed to recuperate at the Wahweap State Fish Hatchery. After one week of recuperation at the hatchery, the fish were transported by truck directly to the stocking sites and released. General Tracking: Annual Summaries 1997 - All ten of the radio tagged fish were contacted between two and eleven times (Table II). The last contact date occurred 64 days after release on December 23, 1997 (Table 11). Dispersal was primarily upstream with a maximum movement of 1.7 RM upstream. General tracking found that six of the radio tagged fish immediately moved 0.2 RM upstream to a large eddy/pool complex beneath Dewey Bridge (Figure 15). One fish moved approximately one mile upstream to a mid-channel location. Another fish moved 0.2 RM downstream of the release site and remained 15