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DLSCUSSION <br />Green River flows were greatest in 1995, peaking at 29,800 cfs on June 18. Mean monthly flows <br />in 1995 were above average for the period of record (1906 -present). Flows were extremely low <br />1992 and 1994 with the lowest annual peak (11,000 cfs) recorded on May 14, 1994. <br />Chub reproduction was apparently most successful in 1993 (n= 162) when the greatest project <br />CPE (0.09 fish / m2) was recorded. The 1993 coliort of YOY squawfish also appeared to be the <br />strongest. Back calculation of spawning dates (Kesler et al. 1986) indicates the bulk of that years <br />spawn occurred on or near June 5 when Green River flows were 21,900 cfs. The timing of the <br />Deso/Gray monitoring trips is a bit pre-mature to adequately assess annual chub or Colorado <br />squawfish reproduction. <br />Results of this study indicate the environmental conditions of 1993-1994 benefitted chub <br />recruitment. Age 1 chubs were sampled in relatively good numbers in July, 1994, which is the <br />first time since 1989. Trammel net catch rates suggest the number of adult sized chubs in <br />Desolation has declines as result of the poor recruitment prior to 1993. Catch rates were lowest <br />in 1996, however, flows at the time of sampling ranged from 13,000 to 10,000. These flows <br />definitely compromised trammel net efficiency, which must be considered when interpreting these <br />results. [NOTE: monitoring in 1997 resulted in the highest trammel net CPEs recorded since 1989 <br />- flows ranged from 7000 to 5000 cfs, which appeared optimal. ] <br />A concentration of spawning Colorado squawfish was sampled at the Rabbit Valley (RM 148.8) <br />site in 1994 and 1995. Of the 39 squawfish handled in those two nights of sampling, the <br />overwhelming majority (89.7%) were ripe males with only two suspected ferrates captured, but <br />sampling in adjacent locations suggest the results at Rabbit Valley were indicative of a <br />concentration area not simply fish moving to another location. We suspect that the bulk of <br />Colorado squawfish spawning occurs at, or closer to, Three Fords, however spawning occurs at <br />other locations in the vicinity -with concentration areas changing from year to year. [NOTE: <br />sampling at Joe Hutch @ RM 160.0 on July 18, 1997 revealed the greatest concentration of adult <br />Colorado squawfish (n=34) we have seen in Deso/Gray. Monitoring at Joe Hutch (eleven <br />occasions since 1985; located four river miles upstream of Three Fords) has never revealed a <br />concentration of adult squawfish even when sampling the next night at Rabbit Valley has.] <br />1 <br />DRAFT ~ ~ ~ 16 <br />1~ <br />