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3-1 3. 0 RESULTS 3.1 Summary Of Fish Collections A total of 22 species of fishes, representing II families, were handled during this investigation (Table 3-l). As a percentage of total catch, the most common species caught were red shiner (57.73%), channel catfi.sh (20.52%), and cORlllon carp (11.26%). These three introduced species made up 89.51% of the total catch. Of the 22 fi sh spec ies recorded, 15 are introduced and on1 y 7 are native. As a percentage of total catch, the ratio of introduced to native species was 96.7 to 3.3. The endangered species (Colorado squawfish, 1.97%; humpback chub, 0.04%; and bony tail, 0.01%) made up 2.02% of the total catch. It should be noted that some introduced species were caught below Cataract Canyon, at the upper end of Lake Powell, and not in the ma in river; i.e. walleye, striped bass, threadfin shad, black crappie, kokanee salmon, northern pike. If only the species caught above the influence of Lake Powell are considered, there were 9 introduced species and 7 native species. An adult female kokanee salmon was captured on September 25, 1985, near Imperial Canyon. The fi sh had mature eggs, a1 though sti 11 attached to the ovarian sacs, and she exhibited the rosey spawning colors of the species. Its origin may have been Flaming Gorge Reservoir, 426 river miles upstream on the Green River or the reservoirs of the Currecanti (Aspina1) Project on the Gunnison River, a similar distance upstream. The total numbers of fish captured in each sample and the associated habitat information along with a summary of young-of-the-year, juveniles and adults are presented in Appendix A. The original raw data sheets are included with the six trip progress reports. 3.2 Colorado Squawfish A total of 517 Colorado squawfish were captured during the 6 Cataract tri ps. Inc1 uded were 4 adu1 ts (p1 us 2 found dead from unknown causes and not included in this count), 4 juveniles, and 509 young-of-the-year. Most of the fish captured were returned alive (283 YOY), while the remainder were preserved as larvae to verify identi fication in the 1 aboratory. One adu1 t squawfish died in a gill net and was preserved. The following breakdown by age groups details the capture information and disposition of each fish hand1 ed. 3.2.1 Adults Tabl e 3-2 represents a osummary of the adult Colorado squawfi.sh hand1 ed during the Cataract Canyon Fish Study. 0 Note that two fish were found dead from unknown causes, preserved, and transferred to the U. S. Fi sh and Wildlife Service, consistent with collecting permit requirements. Also, one adult Colorado squawfish, radiotagged by USFWS/Lynn Kaeding, was detected at RM 24.0 (Lathrop Canyon) of the Colorado River on August 24, 1985 at 1510 hours. A strong signal was received on frequency 40.122 on the ATS programable receiver. No attempt was made to capture this fish.