4247

• UCREFRP Catalog Number: 4247
• Author: Pucherelli, M. J. and R. C. Clark.
• Title: Comprehensive Report ‎(1986-1988)‎ on the Effects of Green River Flows on Backwater Habitat Availability as Determined by Remote Sensing Techniques ‎(Remote Sensing)‎.
• USFW Year: 1989.
• USFW - Doc Type: Denver, Colorado.
• Copyright Material: NO

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UNITED STATES GOVERNMENT

memorandum

TO

Memorandum
: Head, Remote Sensing Section

Denver, Colorado
DATE:Apri1 14, 1989

FROM

:Michae1 J. Puchere1li, Environmental Biologist
Richard C. Clark, Applications Specialist - Advanced Sciences, Inc.

su~EcT:Comprehensive Report (1986-1988) on the Effects of Green River Flows on
Backwater Habitat Availability as Determined by Remote Sensing Techniques
(Remote Sensing)

Applied Sciences Referral Memorandum No. AP-89-4-S
Principal Investigator: Michael J. Pucherelli

INTRODUCTION

Fish populations in the Colorado River system have historically been
dominated by endemic species adapted specifically for this river system.
The recent decline in abundance and range of some endemic species has been
sufficient to classify them as endangered by the U.S. Fish and Wildlife
Service (FWS) (Archer et a1. 1984). In response to this situation, the
Colorado River Fishes Project (1979-1981) and the Colorado River Fishery
Monitoring Program (1982-present) were initiated to expand the information
base of endemic species and determine their flow requirements. Studies have
centered on the Green River because it currently has the most viable
population of Colorado squawfish. This remote sensing study focused on
backwater habitat in the Green River as a key element for the survival of
the Colorado squawfish.

BACKGROUND

Following the construction of Flaming Gorge Dam in 1962 the abundance of
endemic fish species in the Green River decreased. These species included
the endangered Colorado squawfish (Ptychocheilus lucius) and humpback chub
(Gila cypha), and the rare but unlisted razorback sucker (Xyrauchen
texanus). The long-term impact of the operation of Flaming Gorge Dam is
unknown. However, the dam has altered the natural state of the Green River
by reducing flood events and their severity, increasing late fall and winter
fluctuations to accommodate peaking operations and in general altering
natural flows throughout the year (Tyus et a1. 1987, Andrews 1986, Graf
1980).

Since 1979 the U.S. Bureau of Reclamation (Reclamation) and FWS have been in
consultation on the effects of various Reclamation projects including the
operation of Flaming Gorge Dam and its effects on endangered fish
populations in the upper Colorado River system. Early studies were
conducted to establish life history and flow criteria information for