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The second method will incorporate radiotelemetry to follow movements of sub-adult and adult Colorado squawfish captured in the 15-mile reach and implanted with LOTEK@ radio transmitters. A land-based tracking station and data logger that constantly monitors and records radio signals from tagged fish in the immediate vicinity will be deployed near the GVIC Diversion Dam. The data logger will provide continuous information on the movement of fish immediately downstream and immediately upstream of the diversion dam. Therefore, this technology will allow researchers to determine when a radiotagged Colorado squawfish passed either up- or downstream past the diversion dam. This automated tracking system is currently being used to evaluate use of the fish passageway by radiotagged, adult Colorado squawfish at the Redlands Diversion Dam on the Gunnison River. Movements of fish will also be monitored by boat, between Price Stubb and GVIC diversions and downstream from GVIC to the Lorna boat landing. If radiotagged fish cannot be located, searches may extend into the 2.3 miles of the Lower Gunnison River upstream to the Redlands Diversion Dam, downstream from the Lorna boat landing to Westwater Wash, Utah, (river mile 124.8), the head of Westwater Canyon, and along the GVIC canal system. Similar techniques were .used to evaluate up- and downstream fish movement following the construction of a grade-control structure by the City of Craig, Colorado, on the Yampa River (Masslich 1993). However. the study design proposed for GVIC varies slightly from the one used at the Craig grade-control structure. A more direct but less preferable means of determining if fish move over the GVIC Diversion Dam would be to have an observer on-site to record upstream movement through the notch. However, this method would be impractical because it would be time consuming and would require extensive observation to note if fish were moving through the notch. Moreover, given that the water clarity is often poor, it would also be difficult to determine what species were moving through the notch. Direct observation might be used on a limited basis if the other planned evaluation techniques are not successful. Sufficient preliminary data may be obtained during the first year of this evaluation to determine if this passageway design would be appropriate to pass native fish at other instream barriers in the Upper Colorado River Basin, e. g., Tusher Wash on the Green River and Hartland Diversion Dam on the Gunnison River. If the first year's preliminary data from GVIC indicate that this design successfully passes native fish, proceeding with the design and construction of passage at these other sites could 'be recommended. This would allow current schedules identified by the RIPRAP for completion of fish passageways at these other sites to be met. VII. Task Description and Schedule Description Task 1. Capture sub-adult and adult Colorado squawfish with electrofishing and implant with radio transmitters. 6