9599

• UCREFRP Catalog Number: 9599
• Author: Miller, W. J. and D. E. Rees.
• Title: Annual Report - Colorado Squawfish Habitat Use and Movement During Summer Low Flow in the Yampa river Upstream of Cross Mountain Canyon.
• USFW Year: 1997.
• USFW - Doc Type: Fort Collins, CO.
• Copyright Material: NO

INTRODUCTION
' An essential part of determining of limiting factors for Colorado squawfish
(Ptychocheilus lucius) in the Yampa River is the characterization of habitat requiretftents
t of that species. There is limited existing information on squawfish habitat use or
movement in the Yampa River during the low flows which occur during late summer.
This study relates to the Green River Action Plan, Yampa River Elements 1.A.2.,
1.AA.a.(3)(a)., and 1.B.2. of identifying base flow discharge needs of endangered fi1§hes
in the Yampa River. The goal of this study is to determine habitat use patterns of
' endangered fishes in the Yampa River during the lowest flow period of the year (i.e,
August through October). The specific objectives of this study include:
' • monitor movements of Colorado squawfish, northern pike and channel catfish its the
Yampa River during the low flow periods (August through October)
' • to determine the range of habitats occupied during the base flow periods.
The specific objectives of this study were to monitor movements of Colorado squadfish
' using radio telemetry to determine: 1) the range of movement during the low flow
period; 2) summer low flow habitat use; and 3) the distance Colorado squawfish moved
' from later summer into winter. In addition, northern pike and channel catfish were also
radio implanted in the same locations and monitored during the monitoring of the
Colorado squawf sh movement.
' In addition to the determination of movement patterns, telemetry data will be used to
compare sites occupied by Colorado squawfish during summer flow conditions to the
' availability of habitat during summer low flow habitat months. The availability of
distinct habitat types will be determined in another portion of the study which measured
' channel cross sections and modeled hydraulics of various water levels to determine] how
habitat changes with flow.
Study Area
The area which the radio tagged fish occupied was the reach from just downstream' of
Signal Butte (RM 103) down to about 2 miles below Maybell bridge (RM 77) thereby
defining the area for this study. The radio telemetry observation data was acquired within
this limited reach. This area was where squawfish have been located in previous years.
Yampa River Radio Telemetry Report Page 1
Miller Ecological Consultants, Inc. January 123, 1997