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<br />(a) Larval-Fish Drift-Net Collections, Colorado and Gunnison Rivers near Grand <br />Junction, Colorado, 18 June through 17 August 1996. <br /> <br />This set consists of 686 larval-fish drift-net collections. Of these, 386 were taken <br />from the Colorado River: 106 at river mile 171.4 (CO-U, upper Colorado--just above <br />confluence with Gunnison River), 104 at river mile 167.8 (CO-R, Redlands), and 176 <br />at river mile 153.7 (CO-L, Loma). The remaining 300 collections were taken from <br />the Gunnison River: 104 at river mile 29.3 (GU-B, Bridgeport), 92 at river mile 5.2 <br />(GU-S, Ricky Schroder's), and 104 at river mile 2.6 (GU-AC, above confluence with <br />Colorado River). Fish were taken in 72% of the collections (495 of686). All <br />specimens received have been cataloged (numbers LFL-31085 through 32243) and <br />stored as part of Larval Fish Laboratory holdings for voucher and future study, <br />possibly including detailed analysis of chub larvae and juveniles for species <br />identification and Colorado squawfish otoliths for age determination. <br /> <br />Overall, the collections contain 3,587 fish (an average of 5 specimens per collection) <br />representing 12 species. This is about half the number of fish collected by drift nets <br />in 1994 (13 species) andjust a quarter of those collected in 1995 (17 species). <br />Minnows (8 species) account for 83% and suckers (at least 3 species) 17% of all fish <br />collected in 1996. All non-cypriniform fish, just 14 specimens, are green sunfish. <br />Native species (3 minnows and 2 suckers) account for 87% of all fish, including 87% <br />of the minnows and 89% of the suckers. Colorado squawfish (52 specimens of which <br />3 are tentative identifications--CS?) account for 1.5% of all fish and are present in 5% <br />of the collections (37 of 686 collections). <br /> <br />The 106 Colorado River collections from the station above confluence with the <br />Gunnison River (CO-U) contain 149 fish representing 8 species. Native species <br />account for 96% of the fish. Percentage compositions for species representing at least <br />1 % of the fish collected are 62% speckled dace, 23% chub, 6% flannelmouth sucker, <br />3% bluehead sucker, 1 % white sucker, 1 % unidentified suckers, and 1 % red shiner. <br />Like 1994, but unlike 1995 collections, no Colorado squawfish were collected at this <br />station. <br /> <br />The 300 Gunnison River collections (3 stations) contain 1,176 fish representing 11 <br />species. Native species account for 83% of the fish. Percentage compositions for <br />species representing at least 1 % of the fish collected are 41 % chub, 20% bluehead <br />sucker, 12% carp, 10% speckled dace, 9% flannel mouth sucker, 3% white sucker, 2% <br />unidentified sucker, and 1% fathead minnow. Colorado squawfish (7 specimens) <br />account for less than 1 % of the catch. <br /> <br />The 280 Colorado River collections below the Gunnison River confluence (2 stations) <br />contain 2,262 fish representing 12 species. Native species account for 88% of the <br />fish, a percentage somewhat intermediate between those for Gunnison River and <br />Colorado River collections taken above the confluence. Percentage compositions for <br /> <br />10 <br />