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species to the Price River. Therefore, this habitat is probably an important refuge for both flannelmouth and bluehead suckers in the Green River basin. Few tagged suckers were recaptured, so the extent of sucker movement from the Price River to the Green River is unknown. Recapture information that was collected showed that most fish stayed within a relatively small area, which is consistent with movement patterns shown by flannelmouth suckers in the White River (Chart and Bergersen 1992). However, the low number of recaptures could have been a result of movement out of the Price River. Such movement was documented for 5 individuals. The Price River produces large numbers of young suckers, and some of these fish do migrate, so it is possible that many of the suckers that are found in the Green River were produced in the Price River. Large numbers of flannelmouth suckers and moderate numbers of bluehead suckers were collected throughout the lower Price River in both years of the study. All age classes of both species were well represented, and catch rates were comparable to other tributaries in the upper basin. This information suggests that high quality spawning, rearing, and adult habitat is available to these species on an annual basis. These data also suggest that Price River populations of these species are stable and self sustaining. These species were once abundant throughout the Colorado River basin, but their distribution has been reduced, and their numbers are still declining in many areas (Yvette Converse, Utah Division of Wildlife Resources, unpublished survey of aquatic biologists working in the Colorado River basin, 1997). If these declines continue, the fish in the Price River and other tributary streams could be important for future conservation efforts. One alarming finding was the absence of roundtail chub, and the extremely low numbers of speckled dace. In addition, no razorback suckers were captured during this study. Razorback sucker was historically abundant in other portions of the Upper Colorado River Basin, but its numbers are now quite low throughout its former range. Therefore, collection of razorback sucker from the Price River was not expected. However, roundtail chub and speckled dace are still fairly common in other parts of the upper basin, and both species were common or abundant in the Price River only 20 years ago (Utah Division of Wildlife Resources, unpublished data). The reason(s) for the elimination of roundtail chubs and the reduction in numbers of speckled dace in the Price River is not clear; existing habitat and water quality seem to be adequate to support both species. However, three possible explanations for these changes are suggested. First, the gauge at Woodside recorded extremely low flows from June through September in both 1977 and 1993. These periods of low flows may have caused water temperatures to increase or dissolved oxygen concentrations to decrease to levels that are lethal to some native fish species. Another possible reason for the decline is the chemical treatment of Scofield Reservoir which occurred in the fall of 1977. This reservoir in the Price River drainage was treated with 1.05 ppm rotenone to remove carp, redside shiners, and Utah chubs (Utah Division of Wildlife Resources, unpublished data). Potassium permanganate was applied below the reservoir to detoxify the rotenone, but problems arose which resulted in rotenone not being detoxified for several hours {Mike Milburn, Utah Division of Wildlife Resources, personal communication). Unfortunately, the effects of this event on native fish were not documented. Finally, several pollution-caused fish kills have occurred in the Price River within the last 20 years (Randy Radant, Utah Division of Wildlife Resources, personal communication). Regardless of the cause of the elimination of roundtail chubs from the Price River, it is not surprising that they have not recolonized the lower portion of the river, because this species 15