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October and relocated at river mile 23.2 in mid-April. Another Colorado pikeminnow was located at river mile 85.5 in late September. These data suggest that some Colorado pikeminnow may remain in the Price River throughout the year, and it i~ likely that the other native species also use the Price River throughout the year. Two Colorado pikeminnow were never relocated after they received radio transmitters. These fish may have been inhabiting areas where a radio signal could not be received, but this is unlikely since the Price River is narrow and does not contain many deep pools or side channels. It is more likely that the transmitters failed or that the fish moved out of the study area immediately after the radio transmitters were implanted. At least three other Colorado pikeminnow made long, downstream movements soon after transmitters were implanted. These movements may have been natural, but it is quite possible that this behavior was a result of stress caused by surgical implantation. Therefore, conclusions based on data collected soon after radio implantation maybe questionable. Nearly all of the Colorado pikeminnow that were captured in the Price River were found along shorelines in runs. However, adult Colorado pikeminnow have been shown to use shallow, slow water (e.g. flooded bottom lands and backwaters) in the Green River (Tyus et al 1984; Tyus 1990}. The Price River has very little habitat complexity, and runs are the most common habitat type found throughout the study section. Therefore, the extensive use of runs in the Price River is probably a reflection of habitat availability rather than preference of this habitat type. At least one radio tagged Colorado pikeminnow moved into the Green River in the fall after spending the spring and summer in the area around Woodside. Similar behavior has been noted from Colorado pikeminnow in the Duchesne River. TJtah Division of Wildlife et al. (1999) followed four radio tagged Colorado pikeminnow in the Duchesne River for at least one year. These fish also moved into the Green River in the fall, and none of them returned to the Duchesne River until the following spring. Movement of flannehnouth suckers from the Price River to the Green River was also documented, and a Colorado pikeminnow that was marked in the Green River was found in the Price River. The timing of these movements is unknown, so the cause of these movements is also unknown. However, such movements do show that some of the native fishes that inhabit tributaries to the Green River spend at least some portion of their life in the Green River, so gene flow between the Green River and its tributaries is probably quite high. Successful reproduction of suckers was documented, but spawning of Colorado pikeminnow was not documented in the Price River. The Green River was cooler than normal in 1997, and Colorado pikeminnow reproduction was lower than normal in that system (Melissa Trammell, Utah Division of Wildlife Resources, unpublished data). Temperatures in the Price River were also lower in 1997 than in 1996, which may have had an adverse effect on reproductive success in this system as well, if reproduction occurred. Due to the limited amount of nursery habitat available, inefficiency of the sampling gear used, and poor spawning conditions present during 1997, the lack of documentation of successful spawning of Colorado pikeminnow is not surprising. However, the Price River warms earlier than the Green River, and may attract native fish from the Green River that are searching for suitable spawning and/or feeding areas. The lower 20 miles of the Price River contain numerous rapids with gravel, cobble and boulder substrates. Colorado pikeminnow eggs and larvae require interstitial voids (Lamarra et al. 1985), but detailed habitat measurements were not made in rapids, so it not known whether suitable spawning areas are available. Typical spawning areas, 13