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consisted mostly of sand and boulders and depth averaged 1.3 m at the <br />point of fish capture. Average water temperature in habitats yielding <br />humpback chub was about 180C. Humpback chubs were not collected in riffles <br />and rapids. <br />Adult humpback chubs were captured by angling with native foods <br />(e.g., Mormon crickets Anabrus simplex and megalopteran larvae) in the <br />larger shoreline eddies, at the surface, in the water column, and on the <br />bottom. We observed humpback chub and other fishes (e.g., roundtail chub, <br />common carp Cvprinus carpio) feeding on Mormon crickets at the water <br />surface. Stomachs of two humpback chub that died in trammel nets contained <br />hymenopterans and plant debris; and gross examination of fecal material <br />taken from live fish indicated use of hymenopterans and other terrestrial <br />insects (e.g., Mormon crickets) as foods. <br />Eleven of 76 Carlin-tagged humpback chub were recaptured from 1 week <br />to 2 years following initial capture (five recaptures within one year, six <br />recaptures from 1 to 2 years). Ten recaptured fish were taken in the <br />immediate vicinity of the original capture, but one recapture was <br />collected about 8 km downstream from its initial capture site. Eight <br />recaptured fish (73%, N=11) were captured in breeding condition on at <br />least one occasion. We detected no growth in recaptured fish. <br />About 220 (N=29) of the humpback chub we captured were juveniles (88- <br />228 mm TL). These fish were most often collected in rocky shoreline runs <br />and small shoreline eddies by electrofishing. However, one dead juvenile <br />(122 mm TL) was taken from the stomach of a 61 cm TL western garter snake <br />(Thamnophis species) that was captured in a backwater near the mouth of <br />the Yampa River. <br />8