8214

• UCREFRP Catalog Number: 8214
• Author: Modde, T., D. Irving and R. Anderson.
• Title: Habitat Availability and Habitat Use of Endangered Fishes in the Yampa River during Baseflow Periods.
• USFW Year: 1997.
• USFW - Doc Type: Vernal, Utah and Grand Junction, Colorado.
• Copyright Material: NO

(Miller and Dees 1997).

Habitat composition was simulated incrementally with flow using the RHABSIM (habitat
simulation) software package (Payne 1995). RHABSIM is a newer revision of the PHABSIM
methodology developed by USFWS (Bovee and Milhous 1978). Stage/discharge relationships were
determined using either the manning equation or the step-back hydraulic method included in the
software package.

Table 3.-Habitat types used to characterize the Yampa River during low flow conditions.

Name/Type Depth (m) Velocity (m/s) Species Use
Class I Pool > 2.0 0.0 to 0.1 Adult Colorado squawfish
Class II Pool 1.0 to 1.99 0.0 to 0.1 Adult Colorado squaw fish
Shallow Pool < 1.0 0.0 to 0.1 na
Deep Run > 0.8 0.1 to 0.625 Adult Colorado squawfish
Shallow Run 0.0 to 0.79 0.1 to 0.625 na
Fast Riffle > 0.0 > 0.625 na

Results

Cluster Locations

Eleven clusters were measured in 1996, one in strata 2, two in strata 3, two in strata 4, and four
in strata 6, and two in strata 8. Locations, dates, measured flow and flow recorded at the Maybell
gage is given in Table 4. In general the measured flow was higher than the gage. The Maybell
diversion is located at River Mile 89.5 and typically diverts up to 100 cfs. The Maybell gage is
located at river mile 85.8.

Table 4.-Comparison of flow from the Maybell gage to flow measured at each habitat cluster
location, Yampa River, Colorado, 1996.

Field Gauge
Habitat River Flow Flow
Strata Cluster Mile (cfs) ( cfs) Date
2 1 23.9 329.5 383 11/06/96
.., " 10/22/96
1 I 45.5 399.0 4"''''
.J I .J.J
I

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