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Table 1. Summary of capture information for nine chubs recaptured in Deso/Gray Canyons of the Green River, Ut; 1992-1996. RECAPTURE ORIGINAL CAPTURE Spp. PIT # Date RM TL Date RM TL CH '7F7DI52F49 930823 184.8 337 920910 184.8 332 CH ~03180C 930825 175.3 315 910712 175.3 282 CH ~Frolsossa 930828 160.0 277 920709 160.0 268 RT 7F7Da76A41 940704 145.3 309 930830 145.3 309 CH ~aasab 940704 145.3 287 930830 145.3 278 CH ~~034 950724 184.8 284 920708 184.8 256 7F/D243B26 950730 145.5 307 930830 145.5 278 CH IF4I3A3333 960627 184.6 249 950724 184.6 242 RT F IF53157009 g60701 145.5 400 950730 145.5 397 Low velocity habitat sampling conducted during these July sampling trip revealed weak de ' 'es of YOY Gila spp., with the greatest abundance observed in 1993 (Figure 5). index of . ~~~ ,Z~ relative abundance of YOY chub to red shiner was also calculated to demonstrate ynamlc between the native and non native component in the backwaters. This YOY chub/red shiner index approached zero every year but 1993, .025, indicating that the relatively good chub reproduction that year was not overwhelmed by red shiner reproduction. Young of the year were collected throughout the canyon in 1993 with the greatest number collected between RMs 160 and 150 (Figure 6.). The 1993 cohort was sampled again in 1994 as Age 1 fish (Figure 7). Since DWR sampling began in 1985, juvenile chubs have be~ed in 1989, 1990 and 1994 with gaps in the population structure (age 1 and age 2 sh) the o er years (Appendix Figure 2). In 1989, the length frequency analysis indicates the prese of a relatively weak 1988 year class, a slightly stronger 1987 year class, and evidence of strong recnlitment from the years prior to 1986. The 1993 year class is the only cohort that appears to have recruited to a juvenile size in substantial numbers since that time. In Figure 7, preliminary data from 1997 sampling is included DRAFT ~ 8