9398

• UCREFRP Catalog Number: 9398
• Author: SWCA, I.
• Title: Feasibility Assessment for a Multi-Species Management Program, Lower Colorado River.
• USFW Year: 1994.
• USFW - Doc Type: Salt Lake City.
• Copyright Material: NO

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EXECUTIVES~Y

I. INTRODUCTION

It is the purpose of this Feasibility Assessment to identify regulatory options related to
endangered species management that might be applied on the Lower Colorado River, and to
discuss their relative merits and estimated costs.

In recent years, the U.S. Fish and Wildlife Service (hereinafter referred to as the Service) has
taken several actions under the authority of the Endangered Species Act of 1973 (ESA)l relative
to the Lower Colorado River corridor. At least thirty-five animal species that inhabit (or once
inhabited) the Lower Colorado River, riparian corridor, or reservoir edges have been listed, or
have become candidates for listing, as threatened or endangered. In July 1989, the Secretary
of the Department of the Interior (Secretary) ordered an environmental impact statement (EIS)
to be prepared for the operation of Glen Canyon Dam. This EIS required a Section 7
consultation with the Service that resulted in a jeopardy opinion and a reasonable and prudent
alternative (RPA) for two endangered fish, the humpback chub and the razorback sucker.2 In
March 1994, the Service designated critical habitaf for the four endangered big river fish
(razorback sucker, humpback chub, bony tail, and Colorado squawfish), an action that affects the
entire Colorado River Basin, particularly the Lower Basin. In 1994, the Western Area Power
Administration (Western) announced changes in the releases into and out of Lake Mohave due
to efforts to sustain the razorback sucker population (Western, 1994a). Currently, the Bureau
of Reclamation (Reclamation) is conducting a "biological assessment" (BA), pursuant to Section
7(c) of the ESA, regarding the potential impact of reservoir and river operations on listed species
throughout the Lower Colorado River Basin. This is being done at the request of the Service,
which informed Reclamation that ".. . current dam operations could have an effect on either the

16 U. s. C. U 1531, et seq., as amended. (See Appendix A for a copy of the ESA)

See Appendix B for a copy of the draft biological opinion on the operation of Glen Canyon Dam and a
revised RPA, dated September 19, 1994.

See Appendix C for the Determination of Critical Habitat; Final Rule (50 C.F.R. 17).

FINAL REPORT

December 20, 1994
Page 1