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a, <br />ABSTRACT <br />This report presents data collected from a single annual monitoring trip in Desolation and Gray <br />Canyons ofthe Green River, UT; 1992-1996. Pre-project n-some cases as early as 1985, is <br />incorporated in o erm comparisons of catch data. Nonnative cyprinids, most importantly <br />Cyprinella lutrensis, accounted for the majority of the catch. Channel catfish (Ictalurus <br />punctatus) was the most abundant species collected in main channel habitats. "Adult and juvenile <br />Gila spp. net catch rates at the four monitoring sites remained below 0.2 fish / 23m net-hour <br />-liroughout this five year period and dropped below 0.1 th efinal year of study, 1996. Low <br />velocity habitat sampling during August, 1993 yielded the maximum catch rate (approx0.1 fish / <br />m~ of YOY chubs. This cohort was sampled in 1994 as Age 1+ chubs and represents the <br />strongest evidence of recruitment since 1989. Colorado_sgnawfish trammel net CPE remained <br />low at the four trend sites, with the greatest catch (0.065 and .08) collected at RM 175.4 in 1994 <br />and 1995. A concentration of eleven squawfish in reproductive condition was sampled at Rabbit <br />Valley (RM 148.8) on July 2-3, 1994. Repeated sampling in 1995 resulted in the collection of 28 <br />Colorado squawfish and this projects highest within-site catch rate, 0.4. Netting catch rates for <br />native catosotmids have declined-since 1989, however rebounded since 1994. Electrofishing has <br />provided a relatively strong sample of both Catostomus latipimus and C. ~ discobolus since 1994 <br />including some strong evidence of recent recruitment. This preliminary analysis indicates the <br />higher flows of 1993 had a positive effect on both reproduction and recruitment of native species <br />while at the same time negatively impacting the resident channel catfish population. <br />t <br />DRAFT ~ i <br />