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. Table 6 ( continued) . TRIP MTES ESTIMATED RIVER FLON (CFS) Cisco Green River cataract . 2 April 11 6,550 4,820 11,520 12 5,920 4,580 11,150 13 6,020 4,820 10,390 . 14 5,840 5,140 11,450 15 6,530 4,580 11,440 16 7,700 4,400 11,780 . OBSERVATIOOS Data Sheets . Field data sheets for trip no. 2 are attached to the end of this report. These data are being entered in the database management system, dBASE 111+ for final analyses and transfer to the BOR and FWS datafiles. Fishes . Although only one adult humpback chub was captured during this trip, the finding was significant. This fish was determined to be a female, based on the shape and slight swelling of her cloaca, her swollen abdomen, and the feel of her egg sacs. She was judged to be in the initial phases of acquiring her nuptual colors, based on the light rose coloration of her paired fins. This finding is not sufficient evidence to designate Cataract Canyon as a "confirmed spawning area" for humpback chub, but it is excellent evidence to suggest that this is the case. . . No conclusions can be made regarding the capture of three juvenile Colorado squawfish during this trip. Since no seining was conducted, no assessment of the survival of the 1987 year class is possible as was done during trip 1. . A significant observation during this trip was the strength of the 1987 year class of channel catfish and carp. Of the 235 channel catfish captured (primarily electrofishing), 80 were hatched last year. The strength of that year class was feared late last summer when seining revealed large numbers of YOY. The channel catfish is a potentially strong-competitor and predator of young endangered fishes along shallow shorelines and backwaters. Also, of 210 carp caught this trip, 6 were from the 1987 year class, which indicates some reproductive success by this species in the canyon. . 7