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spillway basin, rates of escapement were calculated with the assumption that all fish from the <br />evaluation draining escaped from the reservoir after the initial draining (43 smallmouth bass, five <br />walleye, eight yellow perch). The authors felt this assumption was warranted, as it would provide <br />a conservative estimate of escapement. In addition, it was the only objective way to establish <br />escapement rates given all of the unknowns associated with the study. Given this assumption, in <br />2005, smallmouth bass were observed to escape at a rate of 0.0028 fish/AF of spill; walleye <br />escaped at a rate 0.0005 fish/AF of spill; and yellow perch at a rate of 0.0006 fish/AF of spill <br />(total spillage in 2005 was 15,533 AF). Thus, these species do appear to escape, but at low rates. <br />It is important to remember that this is likely an underestimate of true escapement; <br />however, upon comparing escapement at Starvation Reservoir with that observed at Elkhead <br />Reservoir, even an underestimate of escapement would be a relatively small amount. Studies at <br />Elkhead Reservoir have estimated escapement of smallmouth bass at 0.02 fish/AF (Miller et al. <br />2005), meaning that Starvation Reservoir escapement rates are an order of magnitude smaller <br />than those observed at Elkhead Reservoir. For rates of escapement at Starvation Reservoir to be <br />similar to those seen at Fslkhead, at least 310 smallmouth bass would have had to escape the <br />spillway in 2005 compared with the 43 fish that actually did. The largest number of smallmouth <br />bass seen during the study was 184 fish during the initial draining in 2002. This suggests that <br />though escapement over the spillway was probably underestimated, escapement rates at <br />Starvation Reservoir are not likely to be as high as at Elkhead Reservoir. <br />Smallmouth bass escape at slightly higher rates that maybe considered problematic for <br />endangered fish recovery; however, considering its probable self-sustaining population status in <br />the Duchesne River and its definite self-sustaining status in the Green River, escapement from <br />Starvation Reservoir is only part of the overall picture. <br />17 <br />