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<br />samples for identification in the laboratory. Twelve backwaters were <br />sampled according to ISMP protocol, resulting in 24 larval fish <br />samples, No CS were identified in the field, <br /> <br />4. Conduct humpback chub monitoring by placing trammel nets in Colorado <br />River at Black Rocks, Place at least 20 net sets per sampling trip. <br />Electrofish when time permits. Record length and weight data from <br />all captured chubs, check all chubs for existing tags, and PIT tag <br />all new humpback chubs, Seventy-one humpback chubs and 24 apparent <br />roundta i1 /humpback chub hybrids captured by nett ing; 2 humpback <br />chubs, 2 apparent humpback/roundtail chub hybrids, and 4 CS captured <br />by electrofishing at Black Rocks. <br /> <br />5. Perform data summary and analysis, and submit it to the database <br />manager by January 15, 1995, Data have been computerized and given <br />to the database manager. <br /> <br />B. Findings: <br /> <br />Water 1 eve 1 sin the Yampa Ri ver were very low duri ng the peri od for <br />trammel netting backwaters (June 7-10). Consequently backwater areas <br />were mostly dewatered and only one squawfish was captured, Also during <br />this period, the first mile of each five mile ISMP reach was <br />electrofished and as many fish were captured as possible to survey the <br />composition of the overall (sympatric) fish community. Above Cross <br />Mountain the majority of suckers were white suckers and apparent <br />white/flannelmouth and white/bluehead hybrids. Below Cross Mountain the <br />majority of suckers were pure looking flannelmouths and blueheads. Very <br />few white suckers and hybrids were found below Cross Mountain, <br /> <br />A Colorado squawfish reported as injured by electrofishing (large <br />subcutaneous hemorrhage on dorsal surface) on the White River by the <br />Colorado Division of Wildlife in 1992 was recaptured. It was taken from <br />the same area where it was originally captured in 1992 and still had the <br />large subcutaneous hemorrhage. In two years it had increased in length <br />(TL) from 765mm to 788mm, and in weight from 4520 grams to 6300 grams. <br />This fish was tuberculated when captured in 1994. <br /> <br />Recapture rates for humpback chubs have been very low at Black Rocks. <br />This is true for fish marked in previous years, in the previOUS week, or <br />earlier in the same sampling trip. One explanation is that when captured <br />fish are released to the river they leave Black Rocks. Two fish did this <br />in 1994. Both fish were caught in the same net set in Black Rocks, One <br />fi sh was recaptured two days later 15 mil es downstream and the other <br />three days later 16 miles downstream. Both were in Westwater Canyon and <br />were collected by Utah fish researchers. <br /> <br />VII. Recommendations: <br /> <br />Continue trammel netting backwaters on the Yampa River during years of <br />average or above average runoff. Water levels were low in 1992 and 1994 <br />and little was accomplished by the netting effort. However water levels <br />were average in 1993 and a large number of squawfish (25) were sampled. <br />The collection of sympatric fish information should be done periodically <br />but should not conflict with monitoring work for Colorado squawfish. <br /> <br />2 <br />