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<br />future, we expect that at least half of the fish grouped as non-native cyprinids can be <br />identifIed to species with reasonable confidence. <br /> <br />(d) Larval-Fish Drift-Net Collections, Colorado River, Westwater and Moab, Utah, 18 <br />June through 22 August 1996. <br /> <br />This set consists of383 larval-fish drift-net collections received by the Larval Fish <br />Laboratory. Of these, 150 were taken at the Westwater station (river mile 127.5) <br />beginning on 20 June, and 233 at the Moab station (river mile 65.8) beginning on 18 <br />June. All specimens received have been cataloged (LFL 36003-37121) and stored as <br />part of Larval Fish Laboratory holdings for voucher and future study, possibly <br />including measurement of all specimens for length frequency data and detailed <br />analysis of chubs (Gila sp.) and early non-native cyprinid larvae for species <br />identification, questionable Colorado squawfish larvae for DNA verification, and <br />Colorado squawfish otoliths for age determination. <br /> <br />Overall, the collections contain 7,164 fish (an average of 19 specimens per collection <br />received) representing 14 species. Minnows (8 species) account for 85% and suckers <br />(3 species) 11 % of all fish collected in 1996. Non-cypriniform fish, 4% of all fish <br />collected, are channel catfish (Moab only), green sunfish, and a tentatively identified <br />bluegill (Westwater). Native species (3 minnows and 2 suckers) account for 48% of <br />all fish, 44% of the minnows and 99% of the suckers. Colorado squawfish (996 <br />specimens of which 135 are tentative identifications-CS?) account for 14% of all fish <br />and are present in 38% of the collections received (145 of383). <br /> <br />About 4% of all fish were unidentified even to family because of a damaged or dried- <br />out condition (some collections had dried in their original containers while stored for <br />processing). We tried reconditioning some of the dried specimens in 100% ethanol or <br />3% buffered formalin and found that the condition of many placed in formalin did <br />improve (they partially rehydrated) depending on the degree to which they had <br />originally dried. Accordingly, the remaining dried collections were transferred to 3% <br />buffered formalin to better facilitate identification and handling and will remain in <br />that preservative for continued storage (see comments, pages 69-71). <br /> <br />The 150 collections from the Westwater station contain 1,879 fish (an average of 13 <br />specimens per collection received) representing 12 species. Native species account <br />for 86% of the fish. Percentage composition for species representing at least 1% of <br />the fish collected is 40% chub, 27% speckled dace, 15% bluehead sucker, 3% <br />Colorado squawfish, and 1% each carp, fathead minnow, red shiner, sand shiner, and <br />flannelmouth sucker. However, 11% of the fish could not be identified due to <br />damage or drying. Colorado squawfish are present in 17% of the collections (26 of <br />150), were taken from 12 July through 13 August, and measure 6-11 mm total length <br />(TL; most if not all 6-7 mm specimens are from dried collections). <br /> <br />The 233 collections from the Moab station contain 5,285 fish (an average of 23 <br /> <br />14 <br />