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<br />5-3 <br /> <br />project do not come under the protection of the ESA. <br />The four most common fishes captured by all gears combined were the <br />native/endemic species including flannelmouth suckers (37.24%), roundtail <br />chub (29.38%), bluehead suckers (15.21%), and speckled dace (8.25%). <br />Together, these four species made up 90.08% of the total catch. Combined <br />with the fifth native/endemic species (mottled sculpin, 0.52%), the total <br />ratio of native/endemic : nonnative/exotic species in the JH-1 study area <br />was 90.60:9.40. <br />The variations in species composition between the four gear types <br />(Figure 2) demonstrates the appropriateness of using several gears to <br />accurately document species composition for a given reach of river. <br />Electrofishing yielded greater proportions of adults and juveniles, while <br />seining and dip nets yielded primarily juveniles with some adults and <br />larvae, and drift nets yielded primarily larvae and some juveniles. The <br />relative composition of each gear type thus reflects the efficiency of the <br />gear for a given age group or size. Together, the results of these gear <br />types reflect the fish species composition. Nevertheless, with few <br />exceptions, the relative composition of the four gears is similar indicating <br />that the more common species are abundant as all age categories. <br />Of the actively-drifting fishes captured in drift nets at the JH-1 <br />site, five species (bluehead sucker, flannelmouth sucker, roundtail chub, <br />speckled dace, and white sucker) composed 97.71% of the catch. Of these <br />five species, only the white sucker is introduced to the Colorado River <br />Basin, and it appears to be reproducing successfully in this region of the <br />river. <br />