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DRAFT6 <br />comprised an average of 95% of the total number offish collected (Table 1). The majority of <br />those were red shiner, which comprised between 50 and 95% of the total. Other non-native <br />species were collected sporadically and none made up a significant proportion of the total except <br />channel catfish on two occasions. <br />The fourth most abundant species was the Colorado squawfish. Colorado squawfish <br />comprised between 0.09 and 18.9 % of the total, with a mean of 2.09 %. The other native species <br />collected were, in order of abundance, speckled dace (Rhynichthys osculus), bluehead sucker <br />(Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis) and roundtail chub (Gita <br />robusta). Native species, including squawfish, comprised from 0.1 to 24.5% of the total, but <br />only once accounted for more than 6%. <br />Within the habitats sampled during this study, species composition and relative abundance <br />----_ <br />were fairly stable from year to year, with some seasonal changes. The significant exceptions were <br />the large decrease in summer NNC numbers after the 1993 flood, and subsequent dramatic <br />increase in the low-water year of 1994. Native species were found in greater numbers and <br />comprised a slightly greater percentage of the total in all summer sampling periods, but this was <br />always offset by the increase ofnon-native cyprinids by fall. The average species composition and <br />relative abundance for all sampling periods is shown in Figure 2. <br />Table 1. Relative abundance offish species collected in the Green River, RM 57-47, 1992-1996. <br />Native, Non-native cyprinids (NNC) and other non-natives (IVIVI_ <br /> NNC (%) NATIVE (%) NN (%) <br />AVG 95.01 3.11 1.88 <br />STD 9.52 6.13 3.73 <br />MAX 99.87 24.54 12.25 <br />MIN 63.21 .09 .04 <br />.~ <br />-6- <br />