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"... VI' When examining mixed-prey treatments only, there was no difference in percent predation for razorback suckers in single-prey versus mixed prey experiments (separate variance t-tests; p >0.15; Table 6). Considering the difference in percent predation by bluegill, the lack of statistical difference is likely due to the small sample size (n=2); repeating the bluegill test in 2004 appears worthwhile. The mixed-prey tests suggest that bluegill, channel catfish, and largemouth bass do not prefer razorback suckers over fathead minnows, nor that razorback suckers are more vulnerable to predation when in the presence of fathead minnows. CONCLUSIONS CHLP continues to be an amazing place to study. Sadly, it remains the only oxbow community where the early life stages of these two species can be studied. We have uncovered some interesting information but so much more needs to be discovered. There are specific locations or habitat types that are being used by specific live stages. Adult fish are utilizing the entire pond. Spawners of both species are using rock and gravel found along or on the river levee that has been previously disturbed. During the past two years, there has been no evidence to suggest spawning occurs elsewhere. However, in past years when high water flooded the access area, bonytail there were observed exhibiting spawning behavior (M. Thorson, FWS, personal communication). The use of other areas of the pond by spawners, especially at various river stages, cannot be ruled out. These species are remarkably adaptive. The telemetry study revealed that large bonytail utilized the large cavities found in the riprap ofthe high levee during daylight hours. The use of this area by all ten study fish suggests dark cover is an important component of the adults preferred habitat. Historically, large rock talus was rare in this area of the basin, however, woody debris, large snags, root wads, and drift piles were prevalent but have been lost with the deforestation ofthe river's riparian community (Minckley and Rinne 1985). This type of cover appears to be absent from the river today. The use of cavities may have been an effective survival strategy to reduce avian predation, but today, with the presence of channel and flathead catfishes, this behavior may put bonytail at greater risk. These factors merit further examination. Fish larvae and juveniles are routinely found utilizing areas that have dense overhead cover. This preference may have predatory implications. Young fish are most frequently seen in or near beaver den entrances where water depths are normally a meter or more. Small schools of larvae and juveniles were observed sharing shallower habitats with crayfish, which had their claws extended and were actively trying to capture them. Added depth may provide young fish a margin of space or safety. 22