8188

• UCREFRP Catalog Number: 8188
• Author: Muth, R. T., et al.
• Title: Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Forge Dam.
• USFW Year: 2000.
• USFW - Doc Type: \
• Copyright Material: NO

Final Report

1-2

September 2000

temperature regimes and the ecology of riverine biota, including native fishes. Other perturbations
to the Green River system include proliferation of nonnative fishes, water depletions in tributaries,
construction of levees, encroachment of nonnative vegetation, and contamination of surface water
and groundwater.

The 1992 Biological Opinion on Operation of Flaming Gorge Dam (Biological Opinion;
USFWS 1992) concluded that dam operations jeopardized the continued existence of humpback
chub, Colorado pikeminnow, and razorback sucker, and the reasonable and prudent alternative
recommended changes in seasonal releases from the dam (Section 1.3). Those recommendations
were based on the best available scientific information, but the Biological Opinion identified a need
for additional research to better define river flow and temperature regimes that would benefit the
endangered fishes. In 1990, the U.S. Fish and Wildlife Service (Service) and U.S. Bureau of
Reclamation (Reclamation) submitted a proposal to the Upper Colorado River Endangered Fish
Recovery Program (Recovery Program) recommending a cooperative agency approach to further
study the effects of operating the Flaming Gorge Dam on endangered fishes in the Green River
system. That proposal resulted in the development and implementation of the Flaming Gorge Flow
Recommendations Investigation (Chapter 2).

1.1 PURPOSE AND SCOPE

The purpose of this report is to assess flow-habitat relationships of the endangered fishes
and refine flow and temperature recommendations specified in the 1992 Biological Opinion. The
recommendations presented in Chapter 5 are intended to address recovery elements identified by the
Recovery Program. The purpose of the Recovery Program is to recover the endangered fishes while
allowing existing and new water development to proceed in the upper basin. Its overall goal for
recovery of the endangered fishes is to achieve naturally self-sustaining populations and to protect
the habitats on which they depend. The Recovery Implementation Program Recovery Action Plan
(RIPRAP) is an operational plan for implementing the recovery program within the following
elements: (1) identify and protect in-stream flows, (2) restore habitat, (3) reduce negative impacts
of nonnative fishes and sport-fish management activities, (4) conserve genetic integrity and augment
or restore populations, (5) monitor populations and habitat and conduct research to support recovery
actions, (6) increase public awareness and support for the endangered fishes and the Recovery
Program, and (7) provide program planning and support.

Flow and temperature management alone may not be sufficient to ensure self-sustaining
populations of the endangered fishes in the Green River. In fact, a combination of flow and nonflow
management actions will probably be necessary for recovery. It is anticipated that the
recommendations made in this report will not affect the ability of the Recovery Program to
implement other appropriate recovery actions, and that they will facilitate the success of those
actions by improving habitat conditions and enhancing the status of endangered fish populations. In
addition, successful implementation of the recommendations will require consideration of both