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,1.,< .. Dietary Samples. The gut contents of30 fish were collected (photo 8). The 20 fish collected just prior to dawn contained the most material. Samples have not been fully examined but it was obvious they contained crayfish, remains of small fish, vegetation, and small particle debris. The ten fish examined just after dusk contained very little gut contents. We recovered tapeworm contents from 4 (13%) ofthe 30 fish. We occasionally found dead fish. One razorback male was found during the spawning season and there was no apparent reason for its death. I observed a tuberculate and highly fungused male during the telemetry study. The fish spent about 10 min on the surface next to the boat. It appeared the fish was curious about the hydrophone. Fivc dead adults (1 BT, 4 RZB) were found during the week of July 22. Again the fish showed no external evidence of disease, parasites, or wounds. These fish had not bloated and appeared to have died recently. The single BT was a telemetry study fish that still retained its transmitter. The cable ties had left a wound, similar to those fish collected Photo 7. Larval razorback sucker intestinal track filled with 25 daphnia (note eye spots). Photo 8. Gut contents of an adult bonytail being flushed into a pan. earlier. The wound was clean, not inflamed or infected and did not appear to have caused the fishes death. The size of the fish, the fact that they died near or at the same time suggests some event (i.e., lightening, poisoning) may have c,aused their death. PREDATOR/PREY TANK TESTS Few biologists question the predatory role of nonnative fishes. Substantial funding and effort is currently being expended toward the removal oflarge predators, such as largemouth bass, northern pike, and channel catfish (McAda 1997, Jackson and Badame 2002, Modde and Fuller 2002). Unfortunately, systematic research has not been conducted to determine the extent ofthe problem or whether removal is even feasible. 14