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Pump Plant were conducted from June 29 through July 1 and July 6-8, 1993. Electrofishing surveys of the 12 mile reach from Metaska Day Use Area" to the Bradfield Bridge were completed between July 9-13, 1993. The 30+ mile reach of river was divided up into four different segments to facilitate longitudinal estimates of the distribution and abundance of all species of fish collected. Each segment was identified according to the corresponding number of river miles (RM) each study reach was downstream from McPhee Dam. The upper reach (RM 1 - RM 12) was 12 miles long, from the Metaska Day Use Area to Bradfield Bridge. The second segment (RM 12 - RM 17) began at the BLM raft launChing area 0.5 miles downstream from Bradfield Bridge and ended at Doe Canyon, approximately 4.9 miles downstream. The third segment (RM 17 - RM 25) began at Doe Canyon and ended at a campsite approximately 8.2 miles downstream. Referred to as River Mile 13 (RM 13) campsite in this report, the designation is taken from the DOLORES RIVER GUIDE, a 1993 publication that is commercially available to recreational users of the Dolores River. This publication references all river distances in terms of river miles below the BLM raft launch area near Bradfield Bridge. The fourth segment (RM 25 - RM 30) began at RM 13 campsite and ended at the Dove Creek Pump Plant, approximately 5 miles downstream. All fish captured were identified to the species level and measured to the nearest centimeter (em). Length and weight data were collected on most brown, rainbow, and Snake River cutthroat trout, as well as smallmouth bass and roundtail chubs. All fish ~ 15 em (6 inches) captured on the first electrofishing pass through the study reach were marked with a 1 rom diameter hole in the caudal fin, thereby facilitating mark-and-recapture population estimates on the majority of larger species of fish collected during the study. Commencing in April 1991, most trout ~ 20 cm captured during electrofishing surveys within the upper 12 mile reach of river were tagged. A small microfilm- like tag, called a visible implant (VI) tag, approximately 2 rom wide and 4-5 rom long, was inserted under the skin of the fish just behind the eye. The length (ern), weight (g), and a scale sample (for determining the age of the fish) were taken at the time of tagging. Also, the stream segment where the fish was tagged and released was also recorded. This information facilitated studies of the growth, body condition, and movement of VI tagged trout throughout the river within and between water years. All trout captured during the June-July 1993 survey of the 30 mile reach were examined for VI tags. Flooded backwater areas were subjected to seining or electrofishing during the study. These areas generally have warmer water than the main channel and are known to be areas of preferred habitat for many native and non-native fish species, including smallmouth bass, yellow perch, green sunfish, fathead minnows, and carp. RESULTS AND DISCUSSION Species Occurrence The numbers and species of fish collected in the 30 mile reach of 'the Dolores River downstream from McPhee Reservoir between June 29 and July 13, 1993, are shown in Table 2. The smaller species, including mottled sculpin, speckled dace, and fathead minnow were not sampled with the same relative efficiency as the larger species which are more vulnerable to capture by electrofishing. Relative Abundance The relative abundance data (Table 2) was confounded by the fact that many fish, especially rainbow trout and kokanee salmon, were obvious escapees from McPhee Reservoir. Almost 2200 McPhee Lake rainbow trout and kokanee salmon were captured during the 15 day study. Although encountered in far fewer numbers, other species that were obvious migrants" from above the reservoir included smallmouth bass, yellow perch, green sunfish, and Colorado River cutthroat trout. -2-