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

1
EXECUTIVE SUMMARY
' Habitat use data for Colorado squawfish were obtained by tracking five radio tagged adult
fish during July through October, 1996. In addition to the squawfish, five northern pipe and
' five channel catfish were also tagged and located on a bi-weekly basis. All fish were
monitored from River Mile (RM) 77 upstream to RM 103.
' Colorado squawfish used pool habitat the majority of the time that they were observed in
the field. Movement from one pool to another through riffles was documented, however,
no fish remained in the riffles during an observation period. Colorado squawfish moved
' during the late evening to near midnight for what appeared to be feeding within the local
habitat where they were first monitored on the 24 hour observations. No fish during
those 24 hour observations was seen moving through a riffle section but moved actively
' within a longer pool or run habitat. During the course of the study one Colorado
squawfish moved upstream approximately 7 miles. That same fish moved 6 '/2 milejs
downstream to near the point of initial capture by the end of the study. This fish moved
' through numerous shallow riffles and one diversion structure during the lowest floes of
the year. A second Colorado squawfish was noted to move 5 miles downstream and
' remain in that downstream location for the study period.
Channel catfish used pool habitat primarily and run habitat secondarily. Most of those
' fish remained within the same river mile of contact but two had moved approximately 4
miles downstream at the end of the study in late October.
' Northern pike had less movement than any of the other species. They did show
movement during 24 hour periods that were similar to Colorado squawfish with
movement activity peaking after dusk and in late evening to midnight. They did move
' from a stationary location upstream and then back downstream to the location where first
observed. Most of the northern pike stayed within the same river mile where the initial

' capture and tagging took place and did not move outside that area. Most movemen
were less than '/z mile but they did move from pool through a riffle to a pool during ts
the
course of the study.
' Data collection for 1997 should continue as in 1996. Radio telemetry should be
conducted every other week from late July until October. When possible, 24 hour
observations should be made once per month on each Colorado squawfish.
Habitat use information should be based on ground contacted fish locations. Contacts by
' air overflights should be used for general river location to assist ground crews in locating
implanted fish. Ground crews were able to triangulate locations of implanted fish to
verify actual river locations. In some instances the actual locations differed by sev oral
' miles from the location reported by air surveys. The large difference, with no apparent
pattern in occurrence, indicate that air contacts without ground truthing cannot be t ised to

' categorize habitat used by the fish.
Yampa River Radio Telemetry Report Page v
Miller Ecological Consultants, Inc. January 123, 1997
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