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common reason for this generic identification was the size of the fish or the lack of a suite of diagnostic features to determine an identification among Gila species. For the 291 other Gila species captured in the Colorado and Green rivers, habitat data for the actual location of capture was recorded for 269 individuals. Overall, the majority (60%) of other Gila were found in flowing habitats such as shorelines, runs, riffles, and eddies (Tables 9-10). This excludes the capture of 90 small Gila (45-87 mm) while seining one flooded tributary in the Colorado River. As was seen with bonytail, individuals found in flooded tributary and backwater habitats were generally smaller (mean TL 82 mm) than those found in flowing habitats (mean TL 221 mm). This indicates that flooded tributaries are likely an important rearing habitat for juveniles of other Gila species in these reaches. Electrofishing produced the majority of other Gila species captured in both the Green and Colorado Rivers, excluding the one seine haul of 90 juvenile Gila. Electrofishing captures in the Colorado River occurred most frequently in run habitats (48%). While in the Green River, captures in riffle and shoreline habitats (78% combined) were most common. Dispersal of stocked juvenile bonytail Over 98% of all bonytail were captured downstream of release sites on both the Green and Colorado rivers. On the Green River, for all years combined, 85% of all bonytail were captured within 40 RM below the release site, with the remaining 15% distributed fairly evenly down to the confluence with the Colorado River (Figure 10). The pattern was similar on the Colorado River where 94% of all bonytail captures occurred within 30 river miles downstream of the release site (Figure 10). The remaining 5% of captures occurred between RM 29.9 and 70. No bonytail captures on the Colorado River were reported between RM 29.8 and the confluence with the Green River (RM 0). None of the juvenile stocked bonytail were found more than 10 river miles upstream of the release sites. On the Green River, intensive electrofishing efforts for CPM population estimates in 2001 and 2002 provide a closer look at dispersal. The two sampling trips which preceded the 2001 spring stocking found bonytail grouped in areas 0-40 and 80-120 river miles below the release site (Figure 11). These fish ranged in size from 68 to 256 mm, with an average TL of97.7 mm (Figure 12). These fish were all stocked in 1999 or 2000. The final two passes of the 2001 pikeminnow population estimate in late May found the majority of bonytail within 20 RM of the release site (Figure II). These fish ranged in size from 70 to 315 mm, with an average TL of 102.7 mm (Figure 12). Distribution ofbonytail did not appear to be related to the total length. Individuals over 200 mm were found throughout the sampled area. In 2002, twelve bonytail were recaptured after overwintering. These fish were also evenly distributed within the sampling area with no apparent relationship to size (Figure 13). Overall, it would appear that the higher gradient canyon sections, which confine the two release sites, are constraining the movements of juvenile bonytaiL This is further supported by ISMP collections and population estimates for humpback chub in Westwater (1997-2000), Cataract 14