9660

• UCREFRP Catalog Number: 9660
• Author: U.S. Fish and Wildlife Service.
• Title: Colorado Squawfish Revised Recovery Plan - Draft.
• USFW Year: 1990.
• USFW - Doc Type: Denver, CO.
• Copyright Material: NO

DRAFT
EXECUTIVE SUMMARY
The Colorado squawfish (Ptvchocheilus Lucius) was listed as endangered on
March 11, 1967. The original recovery p]an was approved on March 16, 1978.
This is a revision of that plan. The present range of natural populations of
the Colorado squawfish is restricted to the Upper Colorado River Basin (Upper
Basin) in Colorado, Utah, and New Mexico, although hatchery reared Colorado
squawfish have been reintroduced into the Salt and Verde rivers in Arizona.
The Colorado squawfish population has declined from historic levels. This
decline may be due to a combination of physical and biologica] factors.
Physical factors include stream alteration and habitat fragmentation as a
result of dam construction, irrigation, dewatering, and channelization.
Biological factors include competition with and predation by introduced
nonnative fish.
The Colorado squawfish will be considered eligible for reclassification to
threatened when naturally self-sustaining populations are maintained in :the
Upper Basin in the following areas:
(a) the Green River Basin including the Green River from its confluence
with the Colorado River to Echo Park, the lower 220 km (137 miles) of
the Yampa River, and the lower 240 km (150 miles) of the White River;
(b) the Colorado River from Palisade, Colorado, to Lake Powell; and
(c) the San Juan River from Lake Powell upstream to the confluence of the
Animas River near Farmington, New Mexico.
The Colorado squawfish may be downlisted separately by recovery area with the
Green River and the Colorado River areas being downlisted prior to downlisting
of the San Jaun River area. (The Green River and Coloraod River areas should
be reclassified concurrently.)
The Colorado squawfish will be considered eligible for delisting in the
Colorado River Basin when:
(a) downlisting criteria have ,been met;
(b) a population in either the Salt River from a diversion dam upstream
of Roosevelt Lake to Apache Falls or in the Verde River from
Horseshoe Reservior upstream to Palden, Arizona, is re-established
and habitats and flows are protected. Feasibility of this effort
will be re-evaluated at the conclusion of the 1995 Lower Basin
Agreement. At that time the need for inclusion of these areas in the
delisting criteria will be reconsidered;
(c) the threat of significant fragmentation (e.g., fragmentation that
would impair the reproductive success of the population or
limit/impact the adult population size) is removed;
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