7713

• UCREFRP Catalog Number: 7713
• Author: U.S. Fish and Wildlife Service, C. R. F. R. T.
• Title: Colorado Squawfish Recovery Plan.
• USFW Year: 1991.
• USFW - Doc Type: \
• Copyright Material: NO

' EXECUTIVE SUMMARY

' Current Species Status: The Colorado squawfish (Ptychocheilus Lucius) was
listed as endangered on March 11
The original recovery plan was
1967
,
.
approved on March 16, 1978. This is a revision of that plan. The Colorado
squawfish population has declined from historic levels. This decline may be
due to various human-caused physical and biological changes in the Colorado
River system where the fish occurs.
Habitat Requirements and Limiting Factors: The present range of natural
' populations of the Colorado squawfish is restricted to the Upper Colorado
River Basin (Upper Basin) in Colorado, New Mexico, Utah, and Wyoming, although
hatchery reared Colorado squawfish have been reintroduced into the Salt and
Verde Rivers in Arizona. The decline in the numbers and distribution of
Colorado squawfish is due to physical changes in the river system, including
stream alteration and habitat fragmentation as a result of dam construction,
irrigation, dewatering, and channelization. Biological changes including
competition with and predation by introduced nonnative fish also are factors
in the squawfish decline.
Recoverv Ob.iective: Delisting. Each Colorado squawfish Recovery Area
(Recovery Area) can be delisted as recovery objectives are achieved.
Recoverv Criteria: Each Recovery Area will remain listed until such time as
their recovery criteria are met. The species can be downlisted or delisted
when all Recovery Areas have been downlisted or delisted. 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 Recovery Areas:
' (a) the Green River subbasin including the Green River from its confluence
with the Colorado River to its confluence with the Yampa River, 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 Colorado River areas being downlisted
concurrently.)
Th
C
h
l
d
i
l
f
d
l
e
o
en:
ora
ng w
o squawfish will be considered eligib
e
or
e
ist
(a) downlisting criteria have been met;

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