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Fish captured in the spillway during 2004 were generally smaller than those captured in 2003. Fish sizes in 2004 ranged from 27 mm to 297 mm (Figure 9). Total length for black crappie ranged from 29 mm to 109 mm, while bluegill sizes ranged from 27 mm to 110 mm. The majority of the fish captured during the 2004 season were less than 100 mm. One smallmouth bass (98 mm) was captured in the spillway. The time of escapement in 2004 did not reflect a consistent diel pattern, but the rate of escapement did seem to be influenced by stream flow. The highest escapement rates at the spillway were recorded between 6:00 am and 8:00 am on 5 May, and between 6:00 pm and 8:00 pm on 18 May (Figure 10). Discharge at these times was recorded at 344 cfs and 193 cfs, respectively. However, overall catch rate was highest during the week with the highest discharge. Of the 61 fish captured, 60 were collected during the first two weeks when flows were greater than 170 cfs. Only one fish was captured during the last two weeks when discharge fell below 110 cfs. In addition, the majority of the fish were captured in the east spillway net. A total of 48 fish were captured in the east side spillway net as compared to 12 fish in the west side spillway net. All fish captured in 2003 and except for rainbow trout and possibly one 98 mm TL smallmouth bass in 2004 were wild spawned fish. The reservoir was not stocked with bluegill or black crappie in 2003 and 2004. Bluegill has not been stocked since 1986 (B. Elmblad, CDOW personal communication). No tagged smallmouth bass from the Yampa River relocation were captured during the escapement study. In 2003, smallmouth bass were first transferred to Elkhead Reservoir on June 18 after the escapement study sampling ended (Table 5). In 2004, smallmouth bass were transferred beginning on May 4 until July 8. This period coincides with the escapement study but no tagged fish were captured at the spillway. FINAL REPORT - Elkhead Reservoir Escapement, Project No.: 118 Page 9 Miller Ecological Consultants, Inc. May 20, 2005