7028

• UCREFRP Catalog Number: 7028
• Author: U.S. Fish and Wildlife Service.
• Title: Report on the Savery-Pot Hook Project.
• USFW Year: 1976.
• USFW - Doc Type: Denver.
• Copyright Material: NO

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FISH AND WILDLIFE RESOURCES
. Fish
When the early pioneers first arrived on the scene much of
the Colorado River and the lower reaches of some of-its major
tributaries (i.e. the Green and the Yampa) were generally warm and
turbid--but extremely turbulent during the late spring--early
summer runoff period. Only seven endemic (native) species of fish
. --Colorado River squawfish (Ptychocheilus Lucius), humpback chub
(Gila cypha), bonytail chub (Gila elegans), roundtail chub (Gila robusta),
razorback sucker (Xyrauchen texanus), flannelmouth sucker (Catostomus
. latipinnis), and bluehead sucker (Castostomus discobolus)--capable of
living and reproducing in this environment, had survived the process of
evolution.

During the last four decades, a number of large dam have been built
on the Colorado River and its tributaries. As a consequence, many
. sections of this system have been converted from warm, turbid, often
turbulent streams, to clearer and cooler reaches which are less prone to
violent fluctuations, and large, flat-water impoundments. These changes in
. the aquatic environment have created habitat conditions conducive
to certain non-native species of trout, warm-water game fish, and
other fishes, and not as acceptable to some of the highly-specialized
Colorado River endemics.