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DISCUSSION Outlet Stilling Basin In 2002 and 2004, brown trout were captured in quite similar numbers during both drainings (2002: 120 initial/114 evaluation; 2004: 293 initial/349 evaluation). Given that brown trout numbers remained high and that their population is considered stable within the Strawberry River drainage, the most likely explanation is that most are moving into the outlet basin from the river where they are established (though some probably do escape from the reservoir). Influx from the river is especially likely given that no weir was set up between the outlet basin and the river. Largemouth bass were captured in the outlet basin in 2004, though they are rarely encountered in either the reservoir itself or the river downstream of the reservoir (Utah Division of Wildlife Resources 2003). Also beginning in 2004, crews began catching yellow perch in relatively high numbers. Perch were introduced into the reservoir prior to 2002 and are now established in the reservoir. While it is unlikely that walleye, smallmouth bass, and yellow perch are moving from the river into the outlet basin (these species were not found in the river during electrofishing surveys), it is possible that these species escape from the outlet and continue downstream into the Duchesne River. If this were occurring, escapement rates (based on the data collected during this study) through the outlet would be underestimated. Additionally, escapement of the target species may be underestimated as a result of our inability to characterize predation by brown trout in the outlet basin. Given these uncertainties, it was virtually impossible to get a definitive rate of escapement through the outlet works. The outlet drain (capacity = 2,400 cfs) is 117 feet below the reservoir surface when the reservoir is full (5,712 feet elevation). Reservoir operation records from the Central Utah Water 14