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A total of 287 telemetry observations from 10 rainbow trout implanted with radio transmitters indicated no downstream displacement in excess of 0.3 km (0.2 mi) occurred during the high spring flows. Trout movement decreased at discharges greater than 3000 cfs with the least activity at 4500 cfs. The use of side channels increased at flows greater than 1000 cfs. In September, only 3 of 30 trout tagged in February using Visual Implant tags were recaptured below their original capture location. These data also indicated minimal downstream displacement of trout as a result of the high spring flows. No extreme changes in water quality were observed as a result of modified dam operations. Temperature and dissolved oxygen concentrations revealed only slight fluctuations during the spring releases. Elevated nitrogen supersaturation levels were recorded but no symptoms or signs of gas bubble disease were noticed. Although high spring flows reduced the number of anglers using the tailwater in the spring, angling pressure data revealed that overall angler use increased over previous years. A record 292,437 angler hours (73,109 angler days at 4 hr/angler day) were estimated for 1992 on the San Juan tailwater. A catch rate of .84 fish/hour was within the range of catch rates estimated for the fishery since 1986 (.76 to 1.13 fish/hour). Trout population surveys will continue with a sampling effort in September 1993. Additional telemetry studies in a portion of the river having a more constricted flood plain have been postponed until 1994. Water quality monitoring will continue through 1993. A macroinvertebrate study will be initiated during summer 1993. R$SEARCH PROGRAbI MANAGF~NT - The Research Plan recognized the dynamics of resolution of issues regarding current and proposed water development and impacts to the historic and present fish community structures and available habitats. This Program was designed to integrate the various study segment findings as additional data is made available. While specific research topics and time frames for conduct have been identified, evolution of the research will adjust to additions' information needs, as well as ensure completion and assimilation of certain research topics. The second annual report for the San Juan River Research Program will include not only results of research conducted in 1993, but integrate findings with 1991 and 1992 observations. Individual report findings will also be integrated to allow for a more complete view of the presence or lack of a biological response to specific flows. Thus, a continuing process has been developed to address changes in emphasis and additional needs as research progresses. 20