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Table 2. Common and scientific names of the fish fauna collected in the Dolores River from McPhee Dam to the Dove Creek Pump Plant. June 29 - July 13, 1993. Common Name and Number Sampled Scientific Name Brown trout - 935 Salmo trutta Rainbow trout - 2040 Oncorhynchus mykiss Colorado River cutthroat trout - 3 Oncorhynchus clarki pleuriticus Snake River cutthroat trout - 37 Oncorhynchus clarki Kokanee ( sockeye) salmon - 420 Oncorhynchus nerka Flannelmouth sucker - 470 Catostomus latipinnis Bluehead sucker - 36 Catostomus discobolus Roundtail chub - 3 Gila robusta Common carp - 1 Cyprinus carpio Fathead minnow - 9~ Pimephales promelas Yellow perch - 16 Perca flavescens Smallmouth bass - 20 Micropterus dolomieu Green sunfish - 2. Lepomis cyanellus Mottled sculpin - 10. Cot tus bairdi Speckled dace - 10. Rhinichthys osculus Tnese spec~es (due to tnelI small s~ze) were not sampled w~th the same efficiency as the larger species Although stocked in both McPhee Reservoir and the river below the dam, the rainbow trout escapees from the lake were easily differentiated from those reared in the river by their more slender body conformation, silvery coloration, and the loss of a large number of scales. Most likely, scale loss resulted from abrasion incurred during the slide down the concrete spillway. All of the 420 kokanee salmon collected were migrants out of McPhee Reservoir. However, loss of scales did not occur with the kokanee salmon. These migrants out of McPhee Reservoir probably escaped through the bottom release gates. Foraging for zooplankton deep in McPhee Reservoir, kokanee salmon are unlikely to become entrained in the water flowing out the surf~ce spillway. Reinstalled in late-May 1993, the bottom outlet gates were used to control the "managed-spill" from that time through July 5, 1993, when the spill was officially over. The overall body condition of the salmon was much better than that of the lake rainbow migrants. That fact lends credence' to the hypothesis that the salmon left the lake at a later time (and via a different escape route) than the rainbows and had spent less time in the high discharge river envirorunent. Rainbow trout were the most abundant species collected during the survey (Table 2). However, an estimated 86% of the rainbows collected (1763 of 2040) were classified as migrants from the reservoir. Only 277 were classified as stream-reared rainbows resulting from fingerling plants made in the river below the dam. We captured 935 brown trout ~ 15 cm during the study. They were the most abundant species of fish that were considered residents of the river downstream from the dam. The other resident species collected in decreasing order of abundance were flannelmouth sucker, stream-reared rainbow trout, Snake River -3-