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Final Report Study Design . 2-11 for morphometric measurements from photographs. Primary rays of dorsal and anal fins were counted., and ten morphometric dimensions were measured (::l: O.Olmm) with venier calipers~ i.e., depth of nuchal hump, head length, snout length, distance between insertion of pelvic and pectoral fins, maximum body depth, caudal peduncle length, maximum caudal peduncle depth, minimum caudal peduncle depth, length of anal fin base, and length of dorsal fin base (Fig. 2-7). Starting in August 1991, 35-mm photographs, ray counts, and morphometries were taken of every tenth adult captured (excluding recaptures), and videography was discontinued. Adult humpback chub weighing more than 550 g were selected and surgically equipped with II-g radio transmitters from October 1990 through January 1991 and alternate months through March 1993. An effort was made to maintain ten fish with active transmitters during the radiotelemetry phase of the study, and efforts to capture fish and implant radio-transmitters were scheduled according to anticipated extinction times of active transmitters. Other techniques included stomach pumping of adults and scale collection from juveniles. A nonlethal stomach pumping technique was implemented in September 1992 following an evaluation of the technique (Wasowicz and Valdez 1994). Scales were taken from humpback chub less than 200 nun TL to determine age and size at transition from the LCR to the mainstem Other native species including tlannelmouth sucker, bluehead sucker, and speckled dace were measured for total length and standard length and weighed. Non-native species were also measured for total and standard length, weighed, examined for reproductive condition and gender, and released. Channel catfish, striped bass, and selected rainbow trout and brown trout were sacrificed for removal of stomachs. Stomachs were preserved in ethanol, placed in labeled whirl-packs, and transported to Leibfried Environmental Senrices in Flagstaff, Arizona for identification and quantification of food items (See Chapter 9 - FOOD HABITS). All fish were examined for anomalous characteristics such as previous marks (e.g., fin punches, fin clips, external fish tags), parasites, wounds, or deformities. Anomalies were recorded in detail on appmpriate data sheets and photographed if relevant to effects of sampling gear or radio-implant procedures. 1) Total length 2) Forked length 3) Standard length 4) Head length 5) Snout length 6) Nuchal hump depth 7) Insertion of pectoral to pelvic fins 8) Maximum body depth 9) Caudal peduncle length 10) Maximum caudal peduncle depth 11) Minimum caudal peduncle depth 12) Base of dorsal fin 13) Base of anal fin 14) Dorsal ray count 15) Anal ray count Fig. 2-7. Morphometries and meristies recorded for adult humpback chub ~200 mm total length.