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a 5 Samplino Gear The three intensive sites above Yampa Canyon were sampled by a 16 foot 15 meter (m)l electrofishing flatboat with 70 horsepower outboard engine and lower-unit jet-shoe described by Wick et al. (1985a). Electrical shocking current was S supplied by a Powergard 5,000-watt, 60-cycle generator and modulated through a Coffelt model VVP-15 control box. Each intensive site in the Upper Yampa was electrofished for 1 hour. The hour was divided equally into 20 minute blocks of 0 morning, afternoon, and evening time periods. Within Yampa Canyon, trammel nets were used in traditional stationary sets or as large seines (termed floating trammels) through riffles, runs, or eddies as described by Wick et al. (1983 and 10 1985a). The nets were 30m and 61m long and 1.8m and 2.4m high. Mesh size was 25 millimeter (mm) inner mesh and either 250mm or 300mm outer mesh. Prior to electrofishing most backwaters during spring intervening sampling, a block net was set across the mouth of the backwater to capture fish that attempted to escape. Angling with brass or silver spoons was also used while conducting the habitat census and occasionaly after sampling intensive sites. Wick et al. 0 (1985a) described the method in greater detail. Occasionally, during sampling, a squawfish would be seen but not captured. These were referred to as observed fish. When there was a positive a identification, standard habitat measurements were recorded to supplement capture data on river mile locations and habitat (depth, velocity, and substrate). Habitat census Radiotelemetry and catch data from 1978 to 1984 were reviewed to determine habitat types most utilized by Colorado squawfish during high flow, spawning S flow, and baseflow periods (Wick et al. 1979, 1981, 1983, 1985a and 1985b). These habitat types were then enumerated and their area estimated concurrently