8208

• UCREFRP Catalog Number: 8208
• Author: Osmundson, D. B., P. Nelson, K. Fenton and D. W. Ryden.
• Title: Relationships Between Flow and Rare fish Habitat in the '15-Mile Reach' of the Upper Colorado River.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

TABLE OF CONTENTS (Continued)
HABITAT AREA AS A FUNCTION OF DISCHARGE ..................... ....... 22
Change in Area of Mesohabitats ..................................... ....... 22
General ..................................................... .......22
Flooded Gravel Pits ............................................ .......22
Backwaters ................................................. ........22
Eddies ..................................................... ........24
Pools ..................... ..................... ........26
Slow Runs .................................................. ........26
Fast Runs ................................................... ........26
Riffles ........... ................................ ........26
Rapids ..................................................... ........26
Change in Habitat Composition .................................. . .. ........ 26
SUMMER AND WINTER FLOW NEEDS .............................. ........ 28

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Habitat Area ...... . ...... ....... ...... , . 28
Summer Habitat Use and Availability ........... . ................. ... . .... 28
Summer Habitat Preference ..................................... ........ 28
Ranking Flow Levels by Weighted Area of Preferred Summer Habitats ... ........ 33
Winter Habitat Use and Availability .. . .......... . .......... . . . . . • . • . . ..... 33
Winter Habitat Preference ...................................... . ....... 33
Ranking Flow Levels by Weighted Area of Preferred Winter Habitats .... ........ 35
Habitat Depth ................................................... ........37
Minimum Flows for Providing Suitable Depth ...................... ........ 37
Eddy Transect ...................................... ........39
Pool Transect .. , .... , .... 39
Backwater Transects ................................. .. . ..... 39
Run Transects ...................................... ........42
Summary .......................................... ........42
Depth in Relation to The Summer-Winter Flow Recommendations ...... ........ 43
Habitat Heterogeneity ....... . ..... ........ 46
Final Considerations for Summer and Winter Flow Recommendations . ...... ........ 47
SPRING FLOW NEEDS ............................................. ........49
Background .................................................... ........49
Stream Bed Monitoring ........................................... ........50
Stream Bed Movement in Relation to Flows ........................... ........ 50
Eddy ...................................................... ........51
Pool ....................................................... ........51
Backwater .................................................. ........51
Isolated Backwater Pool ............................. . ......... ........ 51
Channel .................................................... ........51
Other Geomorphology Studies ...................................... ........ 54
Revisiting the earlier July Recommendations ........................... . .. 55
Recommendations for Spring Flows ...__ ................... ...... • . ...... 58
SUMMARY OF YEAR-ROUND RECOMMENDATIONS .... ............. ....... 65
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