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dry. The search conducted on the morning of August 6 revealed one juvenile carp (approximately 300 mm) and one small crayfish (Decapoda; species not identified). One small fish (which appeared to be anon-native cyprinid) was observed in a pool, but it avoided capture and was not positively identified. The search conducted in the Green River Canal on November 30 revealed one carp (approximately 400 mm total length--all fleshy parts had been consumed by animals and only the head, ribs and spine remained), one speckled dace (60 mm), and one channel catfish (60 mm). Other animals found included two small crayfish (species not identified), seven live and two dead northern leopard frogs (Rana pipiens) and one megaloptera larva (Corydalidae; species not identified). Tracks from humans and other mammals (including what appeared to be domestic dog, coyote, racoon, muskrat, and possibly weasel) and birds (several unidentified species) were also noted in the mud along the bottom of the canal. Searching in the irrigation-drainage canal produced thousands of mosquitofish (Gambusia affinis), one common carp (350 mm) and two channel catfish (approximately 250 mm). Larger numbers of fish were found impinged on the grate in front of the Thayn Power Plant during the time period when the concrete wall increased water velocity in this location. These fish included one razorback sucker, four flannelmouth suckers, one bluehead sucker, and two common carp, which were all positively identified by aquatic biologists. The razorback sucker was ahatchery-reared fish that was hatched in 1995 and stocked on October 26, 1998, at nm 319 in the Green River. This fish was 384 mm long at the time of stocking and at the time of death (May 15, 1999). In addition, 228 unidentified suckers (probably a combination of flannelmouth suckers and bluehead suckers), 85 common carp, three channel catfish (including one that was estimated to weigh over five pounds), and 16 fish that were unidentified were also removed from the grate. Subadu[t Tagging Electrofishing produced 34 Colorado pikeminnow (Table 4) and 12 Gila spp. (Table 5). None of the Colorado pikeminnow or Gila spp. that were tagged during this study were recaptured. Twenty-four additional Colorado pikeminnow were observed and positively identified but avoided capture (Table 4). Two bluehead suckers, four flannelmouth suckers, and two channel catfish tagged during this study were later recaptured, as were a Colorado pikeminnow that was tagged in the Green River in 1996 (Utah Division of Wildlife Resources, unpublished data) and a flannelmouth sucker that was tagged in the Price River in 1997 (Cavalli 1999) during sampling done for other studies (Table 6). Both bluehead suckers, 1 flannelmouth sucker, and 1 channel catfish had moved upstream past Tusher Wash Diversion Dam during a period when discharge ranged from 3,660 to 7,590 cfs. The recaptured Colorado pikeminnow had negotiated the dam at some time since 1996, while the flannelmouth sucker that was tagged in the Price River had moved downstream past the dam at some time since 1997. Electrofishing catch rates for Gila spp. were significantly higher upstream than downstream from Tusher Wash Diversion Dam; catch rates for bluehead sucker were also much higher upstream than downstream from the dam, but the difference was not statistically significant. Catch rates for Colorado pikeminnow and common carp were significantly higher downstream from the dam than upstream from it (Table 7). Significant differences in catch rates upstream and downstream of the dam were not noted for the other species captured, although green sunfish (Lepomis cyanellus) and walleye (Stizostedion vitreum) were only captured downstream from the dam. i