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<br />verification, and Colorado squawfish otoliths for age determination. <br /> <br />Overall, the collections contain 3,350 fish (an average of20 specimens per collection <br />received) representing 12 species. Minnows (7 species) account for 79% and suckers <br />(2 species) 15% of all fish collected in 1995. Non-cypriniform fish, 6% of all fish <br />collected, are mosquitofish (Moab only), channel catfish, and green sunfish <br />(Westwater only). Native species (3 minnows and 2 suckers) account for 42% of all <br />fish, 34% of the minnows and 100% of the suckers. Colorado squawfish (386 <br />specimens of which 37 are tentative identifications- CS?) account for 12% of all fish <br />and are present in 32% of the collections received (53 of 166). About 5% of all fish <br />were unidentified even to family because of a damaged or dried-out condition (some <br />collections had dried in their original containers while stored for processing). <br /> <br />The 49 collections from the Westwater station contain 672 fish (an average of 14 <br />specimens per collection received) representing 11 species. Native species account <br />for 74% of the fish. Percentage composition for species representing at least 1 % of <br />the fish collected is 35% bluehead sucker, 20% speckled dace, 15% chub, 4% <br />Colorado squawfish, and 2% non-native minnow (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). However, 23% of the fish could not be identified <br />due to damage or drying. Also, the proportion of red shiner, sand shiner, and fathead <br />minnow among those grouped as non-native cyprinids might be quite different from <br />those which were identified to species. Colorado squawfish are present in 18% of the <br />collections (9 of 49), were taken from 13 August through 27 August, and measure 6- <br />10 mm total length (TL; most, if not all, 6-7 mm specimens are from dried <br />collections). <br /> <br />The 117 collections from the Moab station contain 2,678 fish (an average of 23 <br />specimens per collection received) representing II species. Native species account <br />for 34% of the fish. Percentage composition for species representing at least 1 % of <br />the fish collected is 59% non-native cyprinids, 13% Colorado squawfish, 10% <br />bluehead sucker, 9% speckled dace, 2% each red shiner, sand shiner, and <br />mosquitofish, and 1 % each chub and fathead minnow. Again, the proportion of red <br />shiner, sand shiner, and fathead minnow among those grouped as non-native <br />cyprinids might be quite different from those which were identified to species. <br />Colorado squawfish are present in 36% of the collections (44 of 123), were taken <br />from 10 August through 31 August, and measure 6-11 mrn total length (TL). <br /> <br />As noted above, some collections include large numbers of early red shiner, sand <br />shiner, and fathead minnow larvae. To save time and remain within budget, many of <br />these fish, especially those in Moab collections, have been grouped as non-native <br />cyprinids rather than separated to species. Also, taxonomic criteria are currently <br />inadequate to positively identify many of the fish measuring 5 mm or less-red shiner <br />and sand shiner are especially difficult (a detailed comparative description of recently <br />hatched stages of these species might resolve the problem). Still, if needed in the <br /> <br />13 <br />