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,~ .... Tank tests revealed an alarming predation rate for small nonnative predators that included crayfish, amphibians, and fish. Small predators are far more numerous, have easier access to shallower and more densely vegetated habitats than their larger cohorts. They are also relatively immune to most mechanical removal techniques. It is becoming painfully obvious that nonnative predation is an ovelWhelming obstacle to recovery that we may never fully resolve. Bonytaii school, and the size of these schools decrease with age. Relatively large (> 100 fish) schools of larvae and fry were found under the protection of overhead cover. Vie also observed tight schools of small (<10 em) bonytail that numbered up to 50 fish. Schools of older juveniles (10-15 em) were fewer in number and more dispersed in nature. The undelWater camera occasionally captured bonytail >20cm, but these events were rare (5 fishlhour). One event involved a small sehool (5) oflarge adults. Bonytail of all sizes were cover,..oriented and nocturnal in nature. While we observed bonytail using the deeper portions of the pond during the day, their numbers dramatically increased at night. They often fed on the surface and by using spotlights we could detect them throughout the water column, where we presume they were feeding on larger plankton. Larger fish (>30 em) were far more rare and were only observed at night. One large bonytail was observed attacking and driving a relatively large crayfish from a spawning site. Next Years Work Telemetry equipment will be used to further describe the daily behavior and use of cover by bonytail. We are examining the possible use of extremely small transmitters on juveniles (15-20 em). The goal would be to determine behavior and diel movements, especially in terms of habitat and cover use. This work is planned for the next two years. Sampling will increase in an effort to gather more information pertaining to growth rates and habitat use. We plan to use large winged hoop nets to determine the movement of various life stages ofbonytail and razorback sucker. We plan to examine the gut contents of more bonytail to get a better handle of the extent of the tapeworm infestation and to determine what smaller bonytail are eating. Sampling will also incorporate fish acoustics in an attempt to gather more data pertaining to daily movements, densities, sizes, and spatial distribution. We are planning a minimum of 4 seasonal surveys. Tank experiments will continue to examine potential small predators of razorback sucker. We plan to conduct additional tank tests examining the rate of egg and larvae predation by tadpoles as well as possible behavioral differences between razorback sucker and bonytail juveniles. We also plan to conduct experiments examining the interactions of large and medium sized predators in relationship to larval native fish losses. 23