WSP00505

• File Number: 8220.104.I
• Description: Flaming Gorge
• State: UT
• Basin: Yampa/White/Green
• Date: 7/31/1991
• Author: USDOI-USFWS
• Title: Habitat Use and Streamflow Needs of Rare and Endangered Fishes in the Green River-Utah
• Water Supply Pro - Doc Type: Report/Study

Table of Contents

PREFACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Environmental Setting...................................................
Green River Basin Fishes................................................

FLAMING GORGE STUDIES......................................................

Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Study Abstracts.........................................................

Study 1: Summer and fall requirements of age-O Colorado
squawfi sh in the Green Ri ver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Study 2: Winter habitat and flows for adult and young Colorado
squawfish and adult razorback sucker.........................
Study 3: Spring and early summer flow requirements of Colorado
squawfish, razorback sucker, and humpback chub................
Study 4: Fish community interactions of endangered and introduced

fishes....................................................... .
Study 5: Trophic dynamics and ecological interactions in important

backwater habi tats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Study 6: Mapping of important backwater habitats of Colorado

squawfi sh. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HABITAT USE AND STREAMFLOW NEEDS OF COLORADO SQUAWFISH, HUMPBACK
CHUB, AND RAZORBACK SUCKER.............................................

Colorado Squawfish.....................................................
Adu 1 t. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Migration......................................................... .
Spawni ng. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
larvae and postlarvae..............................................
Juveniles......................................................... .

Humpback Chub..........................................................
Bony tail Chub..........................................................
Razorback Sucker.......................................................

SUMMARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Genera 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spri ng. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Summer................................................................................................................................ ..
Autumn and Winter......................................................

RECOMMENDATIONS........................................................... .

Flow and Temperature...............................................

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