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
(Figure 3). The Recovery Team has adopted this report and has recommended
that a similar document based on appropriate criteria be developed for the
Lower Basin. Because Colorado squawfish have been extirpated from the Lower
Basin, criteria would be established primarily to identify priority areas for
research and recovery.
Priority Areas for Recovery-
The highest priority Colorado squawfish recovery areas occur in the Upper
Basin, and include, in order of importance, the Green, Colorado, and San Juan
subbasins. The Green River subbasin includes the mainstem Green, Yampa,
White, and Duchesne rivers. The Green River subbasin contains the largest and
most viable population of squawfish in the Colorado River basin (Tyus 1990).
As such, the Green River and its tributaries constitute the highest priority
site for recovery and maintenance of Colorado squawfish.
Fewer squawfish are found in the Colorado River. However, occurrence of adult
and larval fish has been documented annually since at least 1979. Recovery of
the species in the Colorado subbasin requires the protection of the Colorado
River. If stocking proves to be a successful technique,- then augmentation of
existing populations in the Colorado River may be necessary. to provide
sufficient numbers of fish for successful reproduction and effective
management.
Recent studies indicate that the San Juan River contains a small, reproducing
population of Colorado squawfish. This river may be especially important if
recovery efforts fail on the Colorado or portions of the Green rivers.
Augmentation of existing populations of Colorado squawfish in the San Juan
River also may be necessary to provide sufficient numbers of fish for
successful reproduction and effective management. This should only be done
after the genetics of the San Juan population are documented and if it is
determined that the current population is not viable. 8roodstock should be
taken from the resident population and-young reared for eventual
reintroduction into the San Juan River.
The Lower Basin no longer has naturally occurring Colorado squawfish. Much of
the habitat in the Lower Basin has been severely altered and contains
relatively large populations of introduced fishes. Of the remaining habitat
in the Lower Basin, the upper Verde and upper Salt rivers are most pristine,
and thus offer the best opportunities for reestablishment of Colorado
squawfish. Colorado squawfish in those rivers have been designated
nonessential experimental populations (U.S. Fish and Wildlife Service 1985).
In addition, there is an active proposal by the Service to reintroduce
Colorado squawfish into the mainstem Colorado River between Parker and
Imperial dams and designate them a nonessential experimental population. The
nonessential experimental designation allows stocked fish to be treated as
threatened species. For purposes of Section 7, any experimental population
.occurring within a National-Park or National Wildlife Refuge is treated as
threatened. Outside of National Parks or National Wildlife Refuges, any
experimental population is treated as a proposed species for Section 7
purposes.
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