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3-11 3.3 Humpback Chub A total of 11 humpback chub were captured during this investigation. This total included 2 adults, 1 juvenile, and 8 YOY. The two adults and one juvenile had strong characteristics of G. cypha, and were considered good representatives of the species. The 8rOY were identi fied by the Larval Fish Laboratory as "possibleG. cypha"; techniques to definitively identify the three species of Gila 01 the Colorado River have not been fully developed, and taxonomists prefer to label most specimens as "possi bl e" or "tentative". A metal detector was not available during this investigation to examine humpback chubs for coded wire tags as a way of confirming recapture of the 7,600 fingerlings released by USFWS in December, 1981. One adult humpback chub (tag no. 3l53) and the juvenile were sacrificed for examination, but neither was carrying a coded wire nose tag. 3.3.1 Adults Two adul t humpback chub were handl ed; one near the upper end of Cataract Canyon (at Spanish Bottom) and, the other two in the central region of the canyon. One of these adults was sacrificed as a voucher specimen and to exami ne the fi sh for a coded wi re nose tag. Tabl e 3-6. A summary of the adult humpback chub handl ed d u ring the Cataract Canyon Fish Study. Sam p 1 e River River Date Tlme Gear Habitat Sex TL WT Tag Mil e start-end mm g ( red) ELE034 CO 206.6 850810 0800-0836 EL SCSH 280 175 3153a ELE058 CO 206.0 850924 1050-1111 EL MCSH 334 220 3104b 3.3.2 Juveniles af1Sh sacrlflced for voucher and examlned for coded Wlre tag; transferred to ~SFWS. fish released alive after tagging One juvenile humpback chub was collected in -Cataract Canyon. The fish came from the middle of Cataract Canyon at river mile 207.3, a reach of the canyon which yielded several_ other endangered fishes. The fish was sacrificed and transferred to .the USFWS,.and was not found to be carrying a coded wire nose tag.