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6 5 --....-....-.....-..- ........ .-.-................. n = 84 4 - .. - . - >- u :z UJ => 3 0 UJ a:: LL 2 1 o 30 40 50 60 70 80 TOTAL LENGTH (mm) 90 100 Figure 3. Length frequency histogram for age-O and juvenile Colorado squawfish captured in the Lake Powell inflow, 1993; Nine larval Colorado squawfish were captured in larval light traps during post-runoff sampling. Two fish were captured at Gypsum Canyon (RM 196), two were captured at Dark Canyon (RM 183), and five were captured at Sheep Canyon (RM 177). 4.4.2 Gila sP. One Gila. measuring 56 mm TL, was captured seining near Palmer Canyon (RM 195) during pre-runoff sampling. During post-runoff sampling 32 Gila, ranging in length from 24-43 mm TL, were captured by seining. Chub were typically found along steep sandy shorelines from Imperial Canyon (RM 200) to Clearwater Canyon (RM 192). One chub, measuring 28 mm TL, was captured during post-runoff sampling in a light trap at Gypsum Canyon (RM 196) Chub were too small to identify to the species level, however dorsal and anal rays were counted on two of the larger chub. DorsaUanal ray counts on these fish were 9/10 and 10/10 (similar to modes reponed for humpback chub and bonytail). Ray counts for the 28 mm chub caught in the light trap were 9 dorsal and 9 anal (typical of roundtail chub). 4.4.3 Razorback Sucker Fifteen suckers captured in the Lake Powell inflow have been preliminarily identified as razorback suckers by the Larval Fish Laboratory at Colorado State University. The initial identification of these fish was based on morphology. Conclusive identification is pending the results of DNA analysis. All fifteen fish were captured by the NPS on June 21 - 22, 1993. These fish were captured at Sheep Canyon (RM 177) with larval light traps. 12 I I I I I I I I I I I I I I I I I I I