8249

• UCREFRP Catalog Number: 8249
• Author: Modde, T., W. J. Miller and R. Anderson.
• Title: Determination of Habitat Availability, Habitat Use, and Flow Needs of Endangered Fished in the Yampa River Between August and October.
• USFW Year: 1999.
• USFW - Doc Type: Project #CAP-9,
• Copyright Material: NO

List of Figures

Figure 2.1 Annual hydrograph for the Yampa River, Maybell gage for 10%, 20%, 50%, 80% and 90% of

exceedance flows. ....................................................................................................... .........................21

Figure 2.2.Flow frequency curve for minimum mean average daily flow for 82 years for the Maybell

gage. ........................................................................................................................................ ........... .21

Figure 2.3. Seasonal hydrographs for the driest (1934), 75% exceedance (1919), median (1967), 25%
exceedance (1920), and wettest (1997) years recorded on the Yampa River, Maybell gage..............22
Figure 2.4. Fall hydro graph for the Yampa River, Maybell gage showing percentile flows .....................22
Figure 2.5.Y ampa River Study Area. ....................................................................................................... .24
Figure 3.1. Fall flows for 1996 and 1997 with reference flows for 50% and 80% daily exceedance. ......41
Figure 3.2. Example of curve break flow (i.e., approximately 80 cfs) representing the point at which
flows decline at the greatest rate relative to the decrease in a given stream profile variable (i.e.,

wetted width).............................................................................................................................. ....... ..43

Figure 4.1. Colorado pikeminnow locations and mean daily discharge, 1996 study period .......................68
Figure 4.2. Colorado pikeminnow locations and mean daily discharge, 1997 study period. ......................68
Figure 4.3a. Locations of Colorado pikeminnow CS855 in river miles during 24-hour observation

(September 9, 1997)................................................................................................................ .............69

Figure 4.3b Locations of Colorado pikeminnow CS855 in feet during 24-hour observation (September 9,

1997) .. ......................................................................................................................... ........................69

Figure 4.4. Habitat use for Colorado pikeminnow during 24-hour observations in the Yampa River,

Colorado. ... .............................................................................................................................. .............71

Figure 4.5. Habitat use for Colorado pikeminnow during daily contacts in the Yampa River, Colorado..71
Figure 4.6. Depth of all habitats used by Colorado pikeminnow during day and night contacts. .............. 72
Figure 4.7. Bottom velocity of all habitats used by Colorado pikeminnow during day and night contacts.73
Figure 4.8. Mean velocity of combined habitats used by Colroado pikeminnow during day and night

contacts......................................................................................................................... ........................73

Figure 4.9. Habitat use during the day for Colorado pikeminnow in the Yampa River, Colorado. ...........74
Figure 4.10. Habitat use during the night for Colorado pikeminnow in the Yampa River, Colorado........74
Figure 4.11. Habitat use for channel catfish during daily contacts in the Yampa River, Colorado. .......... 75
Figure 4.12. Habitat use for northern pike during daily contacts in the Yampa River, Colorado. ............. 76
Figure 4.13. Locations of humpback chub 40.471 recorded every two hours over a 24-hour period at river
mile 35.3 in the Yampa River on 7 August 1997.................................................................................77
Figure 4.14. Locations of humpback chub 40.442 recorded every two hours over a 24-hour period at river
mile 18.1 in the Yamp River on 8 August 1997......... ........ .................................................................. 77
Figure 4.15. Macrohabitatats used by humpback chub in the Yampa River (1986-96). ............................79
Figure 4.16. Channel location in which humpback chub were collected in the Yampa River. .................. 79
Figure 4.17. Flows and aerial contacts of channel catfish (Ce), humpback chub (HC), and Colorado
pikeminnow (CS) from the Yampa River during the baseflowperiod in 1996 and 1997....................80
Figure 4.18. Distance traveled by radio implanted humpback chub in the Yampa River 1996-97............82
Figure 4.19. Type of activity exhibited by Colorado pikeminnow expressed as percent of time monitored
during day and night contacts.................................................................,............................................ 86
Figure 5.1. Histogram of annual total transgressions (flows below target of 91.5 CFS). Yampa River
near Maybell 1916 - 1995 .................................. .................. ......................................................... ....... 92

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