6028

• UCREFRP Catalog Number: 6028
• Author: Wick, E. J., D. L. Stoneburner and J. A. Hawkins.
• Title: Observations on the Ecology of Colorado Squawfish ‎(
• USFW Year: 1983.
• Copyright Material: NO

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and (3) introductions of non-native species. Extinction in the Green
River Basin could result from similar disruptions. A major portion of
squawfish habitat in the Upper Green River has already been eliminated
by Flaming Gorge Dam. Below the dam, significant seasonal alterations
in temperature and flow occur, and daily fluctuations in water levels
probably impact young-of-the-year and juveniles in nursery areas.
Introduced species, such as walleye and northern pike, could prey on
young and compete with adults for the remaining habitat and resources in
the Green and Yampa rivers. Recently approved dams on the White River
will further reduce habitat and range.
Efforts must be made to mitigate the damage already done. We need
to better anticipate, understand, and mitigate the cumulative impacts of
future development to ensure survival of the Colorado squawfish.
Effects of altered temperature and flow regimes must be better understood.
The importance of adequate flushing flows for maintenance of spawning
habitat must not be overlooked. Quality habitat must be preserved for
all life history stages, along with sufficient distributional range, to
maintain a healthy population. Our observations suggest important
relationships between temperature, habitat use, and reproduction in the
upper portions of the basin. We need to build on this work to confirm
and better define these relationships.
ACKNOWLEDGMENTS
This study was jointly funded by the National Park Service and the
Colorado Division of Wildlife. The U.S. Fish and Wildlife Service,
Colorado River Fishery Project, provided much needed equipment and
supplies through William Miller, Don Archer, and Harold Tyus. Tom