9477

• UCREFRP Catalog Number: 9477
• Author: McAda, C. W.
• Title: Flow Recommendations to Benefit Endangere Fishes in the Colorado and Gunnison Rivers.
• USFW Year: 2003.
• USFW - Doc Type: Project number 54,
• Copyright Material: NO

TABLE OF CONTENTS (Continued)
Page
3.2 Colorado Pikeminnow ...................: .......... .......... 3-14
3.2.1 Distribution and Abundance : .................. .....:.... 3-14
3.2.2 Habitat Use ... ................... ......... .......... 3721
3.2.3 Reproduction ................ ............. .. ........ 3-23,
3.2.4 Growth ............ ..................... ... ...... , .. 3-31
3.2.5 Summary of Seasonal Flow-Habitat Relationships for
Colorado Pikeminnow .. ' .......... ....... ............. 3-34
3.3 Razorback Sucker .............................................. 3-38
3.3.1 Distribution and Abundance ......... , ....... ................ 3-38
3.3.2 Habitat Use ............... ............. .... ... . 3-42
3.3.3 Reproduction ............................ ....... .... 3-44
3.3.4 Growth ... .. ............. ...:............... ...... 3-48
3.3.5 Summary of Seasonal Flow-Habitat Relationships for
Razorback Sucker .......................................... 3-49
3.4 Humpback Chub ............ ................ ............. 3-52
3.4.1 Distribution and Abundance ....... ... .................... 3-52
3.4.2 Habitat Use .......... :. ..... ..................... 3-55
3.4.3 Reproduction ... ....... ................. .......... 3-55
3.4.4 Growth .................. ............, ...... ...... 3-58
3.4.5 Summary of Seasonal Flow-Habitat Relationships for
Humpback Chub ....: ............ ... .......... .. , 3-58
3.5 Bonytail ............... ....................... ...........
3-61
4.0 FLOW RECOMMENDATIONS TO BENEFIT ENDANGERED FISHES ....... ` 4-1
4.1 Summary of Endangered Fish, River Flow, and Habitat Relationships ...... 4-1
4. 1.1 Colorado Pikeminnow ..... ......... ..................... 4-1
4.1.2 Razorback Sucker . ... ....................... ........ 4-3
4.1.3 Humpback Chub .......... .... ... .... .............. 4-4
4.2 Integration of Biological and Physical Processes ....................... 4-4
4.2.1 Goal and Objectives of the Flow Recommendations . ..........:.... 4-5
4.2.2 Hydrologic Categories for Annual Recommendations . .............. 4-6
4.2.3 Basis for Level and Duration of Annual Spring Target
Flows ................ ..................................... 4-9
4.3 Flow Recommendations for the Gunnison River ....................... 4-18
4.3.1 Spring Peaks . ... ........... ........................ 4-18
4.3.2 Base Flows .............. . ..... ......................... 4-22
4.4 Flow Recommendations for the Colorado River Downstream from the
Gunnison River. ....................... ... ..... ..... 4-23
4.4.1 Spring Peaks ....... ... .... ........... ....... ...... 4-23
4.4.2 Base Flows ................... ......... .. ... .... 4-27
Final Report ii July 2003