7984

• UCREFRP Catalog Number: 7984
• Author: Maddux, H. R., L. A. Fitzpatrick and W. R. Noonan.
• Title: Colorado River Endangered Fishes Critical Habitat - Draft, Biological Support Document.
• USFW Year: 1993.
• USFW - Doc Type: Salt Lake City, Utah.
• Copyright Material: NO

final rule, the Service concluded that critical habitat was not determinable at the time of
listing and questioned whether it was prudent to designate critical habitat for this fish.
On October 30, 1991, the Service received a 60-day notice of intent to sue from the Sierra
Club Legal Defense Fund. The notice indicated that the Service failed to designate critical
habitat concurrent with listing of the razorback sucker, pursuant to Section 4(6)(c) of the
Act. A second notice of intent to sue, dated January 30, 1992, was subsequently received.
On December 6, 1991, the Service concluded that designation of critical habitat was prudent
and determinable and, therefore, critical habitat for the razorback sucker should be
designated. Because the intent of the Act is "... to provide a means whereby the
ecosystems upon which endangered species and threatened species depend may be conserved
... ", the Service also decided to propose critical habitat for the Colorado squawfish,
humpback chub, and bonytail. The four endangered Colorado River fishes coexist in the
Basin and much of their habitats overlap.
On May 7, 1992, the Sierra Club Legal Defense Fund filed a lawsuit in the U.S. District
Court (Court), Colorado, on behalf of the Colorado Wildlife Federation, Southern Utah
Wilderness Alliance, Four Corners Action Coalition, Colorado Environmental Coalition,
Taxpayers for the Animas River, and Sierra Club. On August 18, 1992, a motion for
summary judgment was filed which requested the Court to order a final rule designating
critical habitat within 90 days. In opposition to the motion, the Service explained that the
complex analyses, required for designating critical habitat could not be completed until
September 1993. This delay was needed to compile biological and hydrological data, and
conduct an economic analysis for portions of seven western States. On October 27, 1992,
the Court ruled that the Service had violated the Act in failing to designate critical habitat
when the razorback sucker was listed. The Court ordered the Service to publish a proposed
rule within 90 days designating critical habitat for the razorback sucker, and to publish a
final rule "at the earliest time permitted and in accordance with" the Act. The Service
published the proposed rule on January 29, 1993 (58 FR 6578).
In designating critical habitat, the Service followed specific provisions of the Act, which
provide no alternatives on what must be designated. Critical habitat is defined in Section
(3)(5)(A) of the Act to include areas occupied or not that are essential to the conservation of
each species. Conservation is defined in the Act as that needed to bring about the complete
recovery of the species. Therefore, the Act dictates what is included in the proposed critical
habitat designation.
The process for designating critical habitat for the razorback sucker, bonytail, humpback
chub, and Colorado squawfish (referred to collectively as Colorado River endangered fish in
this document) consists of three major steps. The first step was to complete a biologically-
based determination of potential critical habitat areas. This step provided an inventory of
areas needed for the survival and recovery of the species. For the razorback sucker, the
biological determination was based on the primary constituent elements and additional
selection criteria determined by the Service. These constituent elements and additional
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