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I~ 1 mile upstream of the structure and working downstream to the structure. Care was taken not to electrofish radiotagged fish utilizing the sampling reach. ' Netting. Netting was conducted during Trips 1, 4 and 5. Netting was only conducted in the plunge pool complex immediately below the diversion structure. Typically two nets were set during each netting run, one on each side of the main chute so that the nets fished eddy lines between the ' thalweg and large, slow eddies below the structure. Netting was usually conducted during the afternoon and evening. Up to four net sets were made during each of Trips 1, 4 and 5. High densities of drifting filamentous algae, particularly during Trips 4 and 5, clogged nets quickly and ' probably reduced their effectiveness. Handling_Fish. All fish handled through Trip 4 were measured for total length and weighed. ' All fish captured were identified to species by an experienced biologist. Sex of each individual was recorded when possible and expression of sexual maturity was noted when present. All native fish captured that exceeded approximately 150 mm were implanted with a PTT tag. All non-natives ' captured that exceeded approximately 200 mm were tagged with a either a blue or yellow model FD- 68BC Floy tag engraved with a unique serial number. ' No fish were tagged during Trip 5. A subsample of non-native species and game fish were weighed and measured and the remainder tallied as adults, juveniles and young-of--year. Total length and weight were recorded for all native species and recaptures during Trip 5. Radiotelemetry Radiotelemetry was used to track the movements of radiotagged flannelmouth suckers, roundtail ' chub and northern pike that were implanted within 1 mile of the diversion structure. A total of 17 transmitters were implanted during the course of the study, nine in northern pike, seven in flannelmouth suckers and one in a roundtail chub. ' Radiotransmitters and receivers. All transmitters were manufactured b Smith-Root Inc. Ei ht y g Model 10001, 6 volt transmitters, weighing 37 gm and having a 180-day life expectancy were used in ' northern pike. Eight Model 150M, 6 volt transmitters, weighing 13 gm and having a life expectancy of 70 days were used in roundtail chub and flannelmouth sucker. Minimum weights of implantable fish was 1850 gm for northern pike and b50 gm for roundtail chub and flannelmouth sucker. All ' transmitters operated within a 40.600 - 40.700 mhz band. Individual transmitters were identified by unique frequency and pulse rate combinations. Frequencies of individual transmitters were separated by 10 hz. Transmitters with the same frequency were separated by the use of two pulse rates, 40 and ' 60 pulses per minute. Receivers used to radio track fish for this study included the Smith-Root search (SR-4U) and ' standard tunable tracking (RF-40) receivers and the Advanced Telemetry Systems (ATS) Mode12000 programmable scanning receiver. Larsen Kulrod NMO-40 omnidirectional whip antennas and Smith- root directional loop antennas were used with these receivers. Surgical implant of radiotransmitters. Radiotransmitters were implanted surgically according to techniques described by Tyus (1982,1988). Fish were anesthetized with tricaine methanosulfate (MS- ' 222) in a 40-gallon plastic bucket until they could no longer maintain equilibrium. Surgery was performed in a specially designed cradle placed on top of a portable table. Water with anesthetic was