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spillway basin and the river, was known to be effective throughout all but the largest spills from the reservoir. During the 2005, water overtopped a small portion of the weir (estimated to be approximately four to six inches and about one to two feet wide). Because it was such a small section of the spillway channel and because it was on the very top of the water, it is highly unlikely that any fish were able to escape from the spillway basin to the river; however, it is possible and therefore, final escapement numbers in 2005 may be an underestimate of actual escapement. Based on the life stages present in the spillway basin, it is likely that each of the species escaped from the reservoir between drainings except for green sunfish, which are apparently established in the spillway basin. It is also possible that smallmouth bass are established in the spillway basin as there was no spill in 2004 and a number of smallmouth bass between 1S0 and 200mm were captured during the initial draining of 2005. These fish could have been YOY in 2004 and thus would have resulted from spawning in the spillway basin. It is also possible, however, that temperatures in the spillway basin are low enough to prohibit normal growth of smallmouth bass. If this were the case, these 150 - 200mm fish could have been older than YOY in 2004. Whatever the source of these smaller smallmouth bass (escapement or spawned in the spillway basin), these fish are not likely to be the source of YOY fish seen in the Duchesne River. It is more probable that smallmouth bass, in addition to reproducing in the reservoir and the spillway basin are also reproducing in the Duchesne River. Escapement Rates The target species (smallmouth bass, walleye) were found during the initial draining of the spillway basin in 2002 and in almost every subsequent sampling effort. Because it is difficult to differentiate a fish that has escaped from the reservoir from a fish that was spawned in the 16