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I I I I I I I I I I I I I I I I I I I Holden and Irvine (1975) observed largemouth bass and carp throughout our study area and reported largemouth bass were found in breeding pairs. During our survey the river was extremely turbid which didn't allow similar sightings, however, we strongly suspect largemouth may still be found in relatively low numbers. We also encountered two new species: a yellow bullhead and striped bass. While the origin of the yellow bullhead can be questioned, the striped bass undoubtedly came from Lake Powell. Striped bass commonly run up rivers to spawn when water temperatures reach between 15 to 20 oC (Moyle 1976) and are reported to run up the Colorado and San Juan Rivers to spawn (Gustavenson 1982). The fish was an adult and would not have survived summer river temperatures (>27 OC) (McAda et al. 1977, Moyle 1976). The smal1mouth bass (Micropterus dolomieui) is a relatively recent introduction to Lake Powell that could directly and indirectly threaten the Escalante native fishery. While none have been collected or reported, they have established an impressive reservoir fishery making up an estimated 20% of Lake Powell's creel (Blommer and Gustaveson 1997). Smallmouth bass were first introduced in 1982 through a decade long stocking program. Fish were stocked at 21 reservoir locations, which included the Escalante River Arm of Lake Powell (Blommer and Gustaveson 1997). Smallmouth bass are actually better suited for small streams than largemouth bass. Habitats used by smal1mouth bass are quite similar to those used by roundtail chub. In Arizona, smal1mouth bass have replaced roundtail chub populations in the Verde and Salt rivers (Minckley 1973). While smallmouth bass will prey directly on native fish, they also pose an indirect threat by spreading the bass tapeworm. Lake Powell smal1mouth bass have been reported to have a high infestation (Blommer and Gustaveson 1997). RECOMMENDATIONS Monitoring--We recommend that surveys be conducted downstream ofFence Canyon to determine the transition area where non-native fishes become more abundant. The reasons why exotics have been able to expand their range in other streams and not in the middle portion of the Escalante River deserves closer examination. We would recommend that a monitoring program be establish to periodically (about every 5 years) monitor the fish community at selected sampling sites. The mainstem river contained an intact native fish community that could easily be impacted. Sampling Equipment Recornmendations-- The sampling techniques we used worked well in remote reaches where equipment had to be packed in. Seining would be the most effective sampling method during low flows. Our efforts were less effective because of higher than normal flows. 19