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CONCLUSIONS Objectivel: determine the presence /absence of `possible "razorback suckers in past collections of Age 0 fish from the lower Green River (coordinate with LFL) • No additional larval or Age 0 razorback sucker were found in past collections from the lower Green River (R. Muth, pers. comm.). Objective 2: determine presence /absence of spawning razorback sucker in the lower Green River (RK 192 -153) • No adult razorback sucker were collected despite a significant level of effort. Two adults have been collected in the mouth of the San Rafael River since these investigations. The population, or sub-population of razorback suckers in the lower Green River is likely very small - perhaps an order of magnitude less than the middle Green River population. Objective 3: determine presence /absence of larval and Age 0 razorback suckers from RK 192 - 0.0 • Larval razorback suckers were collected in and near the mouth of the San Rafael River both years of the study. Sampling was more productive (N = 44} in 1994 than in 1995 (N = 2). However, the scope of this study did not include an assessment of habitat availability. Therefore, it is difficult to determine if more razorback sucker larvae were produced in the low water year, 1994, when habitat appeared less abundant. Based on the integration of the results of this study with those of other researchers (Muth et al. 1998) it is likely razorback sucker larvae collected during this study were produced in the lower Green River. Sampling intensity needs to be increased and redirected to pinpoint a spawning location. Objective 4: examine historic collections /data from the lower Green River to determine if a downward shift in size distribution is evident in fish from the lower stretches; suggesting local spawning • The ISMP YOY data set (Reach 3) was reviewed. There was greater longitudinal variability in YOY pikeminnow lengths during low flow years. Although, in some years YOY pikeminnow were significantly larger below Millard Canyon than above, the converse was true on nearly the same frequency. Clusters of larger YOY (relative to other members of the same cohort) were found randomly throughout the lower 192 km of the Green River from year to year. This analysis did not support the contention that spawning occurs at the Millard Canyon site. Objective S: determine if Colorado pikeminnow spawn near the mouth of Millard Canyon • No adult pikeminnow were collected near the mouth of Millard Canyon either year of study. 10