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cutthroat trout, bluehead sucker, smallmouth bass, yellow perch, roundtail chub, Colorado River cutthroat trout, and common carp. . Several species, too small to be efficiently sampled by electrofishing equ~pment, were incidental captures during the survey, including mottled sculpin, speckled dace, green sunfish, and fathead minnows. Lonqitudinal Distribution by River Seqrnent Numbers of fish species captured by river segment are tabulated in Table 3. Stream-reared "wild" rainbow and brown trout were the most uniformly distributed species among all stream segments throughout the 30 miles of river sampled. Table 3. Longitudinal distribution of fish numbers by river segment collected in a 30 mile reach of the Dolores River, July 1993. Species River Segments in Miles Below McPhee Dam 1-6 7-12 13-17 18-25 26-30 1-12 1-30 Brown Trout 278 274 112 163 108 552 935 McPhee Rainbows 1015 610 102 20 16 1625 1763 Stream Rainbows 63 55 58 48 53 118 277 Kokanee Salmon 329 51 9 14 7 390 420 Cutthroat trout 25 7 4 5 0 32 41 Flannelmouth 2 181 89 116 82 183 470 Bluehead 2 7 20 3 4 9 36 Roundtail Chub 2 0 0 0 1 2 3 Smallmouth Bass 10 7 3 0 0 17 20 Yellow Perch 11 2 3 0 0 13 16 Of the 1763 rainbow trout classified as lake migrants, 1625 (92%) were captured in the 12 mile reach from the dam to Bradfield Bridge, while 138 were collected between the Bradfield Bridge and the Dove Creek Pump Plant. Similarly, 93% of the kokanee salmon (390 of 420) were collected between the dam and Bradfield Bridge while seven percent occurred downstream from the Bradfield Bridge to the Dove Creek Pump Plant. However, the largest kokanee salmon (44 cm) collected was taken at the confluence with Dove Creek. Sixty-one percent of the cutthroat trout occurred in river segment RM 1-RM 6, 17% between RM 7 and RM 12, while 22% were collected between RM 13 and RM 30. More than 90% of the cutthroat trout were of the Snake River sub-species, while 10 % (4 of 41) appeared to be Colorado River cutthroats that had originated from tributary streams upstream from McPhee Reservoir. Sixteen yellow perch and 20 smallmouth bass were among the non-native warmwater species collected during the survey. Eighty-five percent of the smallmouth bass and 81% of the yellow perch were collected in the first 12 miles of river between McPhee Dam and Bradfield Bridge. Two green sunfish and nine fathead minnows were also collected by seining and backpack electro fishing in backwater areas in river segment RM 13 - 17. The longitudinal distribution data (Table 3) strongly indicates that the vast majority of the fish species numbers that were downstream migrants (from McPhee Reservoir) were highly concentrated in river segment RM 1-12. -4-