9566

• UCREFRP Catalog Number: 9566
• Author: Miller, W. J., D. E. Rees and J. A. Ptacek.
• Title: Final Report - Elkhead Reservoir Escapement Recovery Program Project No.
• USFW Year: 2005.
• USFW - Doc Type: 118, Investigation of nonnative fish escapement from Elkhead Reservoir.
• Copyright Material: NO

Table of Contents
Introduction ...............................
............ ...:................. ... 1
Study Area ............................................................................................................................ 2
Study Goals and Objectives :..................................:.............................................................. 4
Methods ........................................................... . ......................................................................... 4
Results ...............................................:....................................................................................... 8
2003 .....................................................................................................:................................. 8
2004 .........................................:............................................................................................. 8
Discussion ............:.....................................................................:............:............................... 16
...................
Screen Options ............................................................:................................:. .. 17
Conclusions and Recommendations ....................................................................................... 19
Literature Cited ....................................................................................................................... 20
List of Figures
Figure 1. Plan view of spillway ............................................................................................... 2
Figure 2. View of Elkhead spillway looking east .................................................................... 3
Figure 3. View of Elkhead spillway looking west .......:........ .................. 3
.................................
Figure 4. View of outlet net and spillway .............................................:............:..................... 4
Figure 5. Elkhead Reservoir outlet capture net ........................................................................ 6
Figure 6. Net on east edge of spillway ..................................................................................... 6
.......................................... 7
Figure 7. View from above spillway net ........................................
Figure 8. View of placement of east and west spillway nets used in 2004 .............................. 7
Figure 9. Size distribution of all fish, black crappie and bluegill, 2003 and 2004 ................ 11
Figure 10. Fish escapement by time of day sampled for 2003 and 2004 ............................... 12
Figure 11. Hydrograph for Elkhead Creek during the 2003 and 2004 sampling seasons based
on data from USGS Gage 9246400, Maynard Gulch. Sample dates are marked as solid data
point on each line. Average daily flow are taken from the period of record from 1995-2004.
..................................................................................................:.............................................. 13
Figure 12. Number of fish captured versus average daily discharge for 2003 and 2004
escapement sampling ...:....:..................................................................................................... 13
List of Tables
Table 1. Sampling dates for the Elkhead Reservoir escapement study, 2003 and 2004.......... 5
Table 2. Summary of escapement netting at Elkhead Reservoir, 2003 and 2004 ................. 10
Table 3. Total number of fish collected during 2003 and 2004 escapement study ............... 10
Table 4. A comparison offish captured (by week) during each year of the Elkhead
escapement study .................................................................................................................... 14
Table 5. Summary of smallmouth bass stocked in Elkhead Reservoir from the Yampa River
that could have been captured during the escapement study (Source: John Hawkins, CSU,
summary data) ......................................................................................................................... 15
Table 6. Species relative abundance in Elkhead Reservoir 1999 (CDOW 1999) ................. 16
Table 7. Elkhead Reservoirs' species relative abundance 2001 (Miller Ecologica12004)... 16
FINAL REPORT - Ellchead Reservoir Escapement, Project No.: 118 Page iii
Miller Ecological Consultants, Inc. May 20, 2005