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j -1 I I I I I I 1 for the remainder of the study. The fourth pike that was tracked for a significant period moved downstream approximately 3.5 miles between April 27 (Trip 1) and June 7 (Trip 2), where the fish resided for the remainder of the study. Of the remaining five radiotagged pike, three were recaptured and taken by anglers within 20 days following release. One of these fish was not tracked beyond its release location, and the remaining two were located once within two days of being implanted. One had moved upstream approximately 0.5 miles and the other did not move. Two radiotagged pike implanted during Trip 1 were tracked through the second trip. One fish initially tagged at 0.4 miles below the diversion moved immediately downstream about 3 miles. On the following trip the fish had moved back upstream approximately 2 miles. The second fish, tagged above the diversion structure during Trip 1 moved approximately 9 miles upstream by the second trip. These fish were not contacted during Trips 3-5. Angler take is suspected in the disappearance of these fish. One roundtail chub and three flannelmouth suckers were implanted during Trip 1. Two of the flannelmouth were released on the last day of Trip 1 and not contacted subsequently. The third flannelmouth was recontacted twice, once during Trip 1,0.1 miles downstream of its release location. This fish was again contacted during aerial telemetry surveillance at the beginning of Trip 2 approximately 45 miles downstream of its release location. Four more flannelmouth suckers were implanted during Trip 2 and tracked for the duration of the trip. Three of the four fish exhibited downstream movements of 0.4 to 0.5 miles. The fourth fish had not moved by the day after implant. None of the four fish were contacted subsequent to Trip 2. It is speculated that radiotagged flannelmouth suckers all migrated out of the "on-ground" telemetry study area and were occupying habitat too deep to be contacted with aerial telemetry. Fish Aggregations Below Diversion Structure No evidence of aggregations of Colorado squawfish or other fish species was detected below the diversion structure at any time during the study. Netting efforts in the plunge pool below the diversion structure during April, September and October yielded a total of three fISh including one adult northern pike and two adult mountain whitefish. All three of these fish were captured during Trip 1 on April 24 at flows of approximately 1720 cfs. A total of six electro fishing runs were conducted exclusively in the plunge pool below the structure during the study. Two additional electrofishing runs included the plunge pool as part of the sample but were continued into areas downstream because no fISh had been captured. Of the six electro fIShing runs conducted in the plunge pool, two were during Trip 1, one during Trip 2 and three during Trip 4 in September. A total of 53 fISh representing nine species were captured during these runs, seven during Trip 1, seven during Trip 2 and 39 during Trip 4. Of these 53 fish, 15 were YOY, 20 were juveniles and 18 were adults. YOY were all capture during Trip 4 and included 14 smallmouth bass and one rainbow trout. Juveniles were captured during all trips and represented seven species with numbers dominated by mountain whitefish and white suckers. Adults were captured during all Trips and were represented by six species. Mottled sculpin were the most abundant adult fish captured (eight individuals) followed by rainbow trout (4), white sucker (2), mountain whitefish (2) and one each of flannelmouth and bluehead suckers. This adult tlannelmouth sucker and one juvenile northern pike represented the total catch of surrogate species by electroflShing in the plunge pool. 17