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not known whether it remained in the Price River or if it moved into the Green River for the <br />winter and then returned to the Price River in the spring. The other fish that was always located <br />in the Price River was tagged near Farnham diversion in the summer of 1997. One attempt was <br />made to relocate this fish in the fall of 1997, and it was found in a run 3 miles below its release <br />site (Table 11). This fish was tracked for approximately one hour. It spent the entire time <br />moving up and down the river within an area of approximately 0.1 miles. At the end of the <br />tracking period this fish was moving upstream about as fast as a person can walk. <br />Two radio-tagged Colorado pikeminnow moved over 20 miles down the Price River <br />during September and/or October and ended up in the Green River (Table 11). One of these fish <br />was tagged in September 1997 at river mile 38.7 and was found in the Green River Less than a <br />month later. The other fish was tagged at river mile 30.0 in the spring of 1997 and spent the <br />summer and early fall in the area. Sometime in late September or early October this fish moved <br />to the Green River. Another radio-tagged Colorado pikeminnow was tagged and released at river <br />mile 35.0 in June 1996 (Table 11). This fish began heading downstream immediately and <br />probably moved over nine miles during the first four days after the radio was implanted. This <br />assumption is based on the fact that the river was searched nine miles above and nine miles <br />below the release point, but the fish was not located. Several other attempts were made to find <br />this fish, but it was not relocated until August. At that time, it had moved into the Green River, <br />where it remained until mid-October. No further attempts were made to locate this fish after that <br />time. <br />Growth rates of the three recaptured Colorado pikeminnow were quite variable, ranging <br />from 0.03-0.29 mm/day. All three fish were similar in size at the time of initial capture (448 to <br />487 mm). Two of these fish are known to have spent at least a portion of the time between <br />capture and recapture in the Green River, while the other fish was captured and recaptured in the <br />Price River. The latter fish had the highest growth rate, but it was captured in the spring and <br />recaptured the same summer, whereas the other fish were captured one year and recaptured the <br />next year. Therefore, the relatively high growth rate achieved by the fish that was captured and <br />recaptured in the Price River can probably be attributed to seasonal differences in growth rather <br />than differences in the biotic or abiotic factors between the two rivers. <br />DISCUSSION <br />Many biologists believed that the Price River had been impacted by humans to the extent <br />that it no longer contained suitable habitat for the endangered fishes of the Colorado River basin. <br />However, collection of 19 Colorado pikeminnow in the lower 45 miles of river, and two <br />individuals above river mile 83 demonstrates that a large portion of the river still contains <br />suitable habitat for this species. Colorado pikeminnow, flannelmouth sucker, bluehead sucker, <br />and speckled dace were documented in the Price River from mid-April through mid-October, <br />even though the habitat parameters that were monitored changed throughout the sampling <br />season, due to natural and human-caused factors. Therefore, suitable habitat for most life stages <br />of native species, including juvenile and adult Colorado pikeminnow, is available for at least half <br />of the year. No data were collected during late fall or winter, so it is not known whether the <br />Price River is used by Colorado pikeminnow or other native fishes during those seasons. <br />However, one of the radio-tagged Colorado pikeminnow was located at river mile 15.7 in mid- <br />12 <br />