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<br />) <br /> <br />specimens per collection received) representing 13 species. Native species account <br />for 35% of the fish. Percentage composition for species representing at least 1% of <br />the fish collected is 56% non-native cyprinids (early larvae offathead minnow, red <br />shiner, and sand shiner that are too small or damaged to be positively identified or too <br />numerous to warrant separation), 18% Colorado squawfish, 9% bluehead sucker, 4% <br />speckled dace, 3% chub, 2% sand shiner, and 1 % each carp, fathead minnow, and red <br />shiner. However, tbe proportion of red shiner, sand shiner, and fathead minnow <br />among those grouped as non-native cyprinids might be quite different from those <br />which were identified to species. Colorado squawfish are present in 51% oftbe <br />collections (119 of 233), were taken from 15 July through 21 August, and measure 6- <br />12mm total length (TL). <br /> <br />As noted above, some Moab collections include large numbers of early red shiner, <br />sand shiner, and fatbead minnow larvae. To save time and remain within budget, <br />many of these fish have been grouped as non-native cyprinids rather than separated to <br />species. Also, taxonomic criteria are currently inadequate to positively identify many <br />of tbe fish measuring 5 mm or less-red shiner and sand shiner are especially difficult <br />(a detailed, comparative description of recently hatched stages of these species might <br />resolve the problem). Still, if needed in the future, we expect that at least half of the <br />fish grouped as non-native cyprinids can be identified to species with reasonable <br />confidence. <br /> <br />(e) Larval-Fish Seine and Light-Trap Collections, Colorado River, Westwater, Utah 6 <br />June through 6 September 1995. <br /> <br />This set consists of 32 larval-fish seine and light-trap collections received by the <br />Larval Fish Laboratory in addition to the 1995 drift-net collections from the <br />Westwater reach of the Colorado River. All specimens received have been cataloged <br />(LFL 35949-36001) and stored as part of the Larval Fish Laboratory holdings for <br />voucher and future study, possibly including detailed analysis of chub larvae for <br />species identification and Colorado squawfish otoliths for age determination. <br /> <br />Overall, the collections contain 283 fish (an average of 9 specimens per collection <br />received) representing 7 species. Minnows (4 species) account for 16% and suckers <br />(3 species) 84% of all fish. There were no non-cypriniform fish. Native species (3 <br />minnows and 2 suckers) account for 99% of all fish, 96% of the minnows and nearly <br />100% of the suckers. Percentage composition for all species in these collections is <br />80% bluehead sucker, 11 % chub, 4% tlannelmouth sucker, 3% speckled dace, 1% <br />Colorado squawfish, 1 % fathead minnow, and 0.4% white sucker. <br /> <br />The six light-trap collections contain 21 fish (an average of3.5 specimens per <br />collection received) representing four species. Minnows (2 species) account for 19% <br />and suckers (2 species) 81 % of all fish. All are native species. Percentage <br />composition for species representing at least 1 % of the fish collected is 77% bluehead <br />sucker, 10% chub, 10% Colorado squawfish, and 5% flannel mouth sucker. The two <br /> <br />15 <br />