7801

• UCREFRP Catalog Number: 7801
• Author: Valdez, R. A.
• Title: Synthesis of Winter Investigations of Endangered Fish in the Green River Below Flaming Gorge Dam.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

TABLE OF CONTENTS
Page
INTRODUCTION ..... ................................................. 1
Purpose ........................................................... 1
Background ........................................................ 1
SYNTHESIS OF GREEN RIVER AND YAMPA RIVER STUDIES ................. 4
River Hydrology And Ice Conditions ..................................... 4
Green River .................................................. 4
Hydrology .............................................. 4
Temperature and Ice Conditions ............................. 11
Yampa River ................................................. 15
Hydrology :............................................. 15
Ice Conditions ........................................... 20
Movement And Habitat Of Radiotagged Adults ............................. 20
Fish Movement And Activity ..................................... 21
Colorado Squawfish ....................................... 21
Razorback Suckers ....................................... 24
Habitat Use ......:........................................... 24
Colorado Squawfish ....................................... 24
Razorback Suckers ....................................... 29
Effect of Flow and Ice on Movement and Habitat Use ........................ 30
LITERATURE REVIEW OF WINTER INVESTIGATIONS ....................... 32
Ice Processes ....................................................... 32
Ice Formation ................................................. 32
Water Temperatures Associated With Ice Cover and Frazil Ice ............ 33
Growth Of Ice Cover ........................................... 33
River Ice Deterioration and Decay ................................. 34
River Ice Breakup and Ice Jams ................................... 35
Effects of Winter Conditions on Riverine Fishes ............................ 36
Physiological Effects ............................................ 36
Effects on Fish Habitat .......................................... 37
Fish Response to Physical and Chemical Conditions .................... 38
Winter Food Sources and Feeding Habits ............................ 38
PRE- AND POST-DAM CONDI'I'IONS ........................................ 40
Hydrology And Ice Processes ........................................... 40
Flow Pattern, Magnitude, And Variation ............................. 40
Stage Changes And Ice Formation ................................. 43
Temperature .................................................. 47
Frazil Ice And Ice Jams .......... ............................. 49
Winter Conditions For Fish ............................................ 49
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