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0 The catch per unit effort (CPUE) of Colorado squawfish in the White River below Taylor Draw Dam (0-167.8 rkm) was 1.43 and . 1.11 fish/hr (Table D1, Appendix) collected during the 1992 and 1993 sampling period. The highest CPUE was 8.46 (1992) and 4.74 (1993) fish/hr collected during the mark recapture work in the first 0.8-rkm (167.0-167.8 rkm) below Taylor Draw Dam. The mean length and weight of squawfish caught in 1992 and . 1993 (573 mm, 1,794 g) was the same as the mean length and weight of squawfish captured between 1985-1990 (578 mm, 1,528 g) (Figure 7, Tables E1 and E2, Appendix). However, the 1992 and 1993 mean length and weight was greater (P<0.005) than the mean length and weight of fish caught between 1977-1984 (478 mm, 899 g). . Using mark recapture methods, it was estimated that there were 26 (±12) and 37 (±18) wild adult Colorado squawfish in the first 0.4-rkm (167.4-167.8 rkm) below Taylor Draw Dam in September 1992 and 1993, respectively. It was also estimated that there were 46 (±24) wild adult squawfish in the first 2.8- rkm (165.0-167.8 rkm) below Taylor Draw Dam in September 1993. 1 Seasonal Macro-Habitat Use of Wild Adult Colorado Squawfish Macro-habitat data were collected from 210 observations of 38 adult Colorado squawfish in the White, Green, and Yampa rivers from 30 September 1992 through 29 October 1993. The macro- habitat data are presented in Table F1 in the Appendix. The majority of squawfish were found in main channel run habitat in Spring, Summer, and Fall, and pool habitat in winter (Figure 8). Other less utilized habitat types included pools in . autumn, riffles in winter, eddies in spring, and backwaters in summer. Cutbank habitat was the primary cover type occupied by squawfish in all seasons (Figure 8). Other less-used primary cover types included open deep water areas in autumn, rocky areas in winter, and aquatic vegetation in spring and summer. The most common secondary cover type was aquatic vegetation, followed by . rock substrates, and cutbanks along the river. Most squawfish were found primarily over gravel substrate (Figure 8) in all seasons. Other primary substrate types over which squawfish were located included bedrock in winter, sand in spring, and rubble in summer. The main secondary substrate over which squawfish were located included rubble, gravel, sand, and cobble. The water depths at which squawfish were found ranged from 0.46-4.57 m (X=2.84 m) in autumn, 0.61-4.57 m (X=4.13 m) in winter, 0.46-4.57 m (X=1.23 m) in spring, and from 0.46-7.62 m (X =1.91 m) in summer (Figure 8). The water temperatures at which squawfish were found ranged from 7-180C in autumn, 12-140C in . spring, and 15-280C in summer (Figure 8). No temperature readings were taken during the winter of 1992-1993. 15 0