8031

• UCREFRP Catalog Number: 8031
• Author: U.S. Department of the Interior.
• Title: Fish and Wildlife Service Final Biological and Conference Opinion on Lower Colorado River Operations and Maintenance - Lake Mead to Southerly International Boundary.
• USFW Year: 1997.
• USFW - Doc Type: \
• Copyright Material: NO

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

BIOLOGICAL OPINION

Table of Contents

Effects of the Environmental Baseline. . . . . . . . . . . . . . . . . . . . . . .. 127
Effects of the Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 137
Cumulative Effects: Bony tail Chub and Razorback Sucker . . . . . . . . . .. 139
Cumulative effects of human population growth . . . . . . . . . . . " 139
Cumulative effects of economic development . . . . . . . . . . . . . .. 139
Cumulative effects of future visitation/recreation ............ 139
Cumulative effects of environmental contaminants ........... 139
Cumulative effects of non-Federally supported
stocking of non-native fish . . . . . . . . . . . . . . . . . . . . " 140
Southwestern Willow Flycatcher ................................ 140
Cumulative Effects: Southwestern Willow Flycatcher . . . . . . . . . . . . " 146
Cumulative effects of human population growth . . . . . . . . . . . " 146
Cumulative effects of economic development. . . . . . . . . . . . . .. 146
Cumulative effects of future visitation/recreation ............ 146
Cumulative effects of environmental contaminants ........... 146
Cumulative effects of wildfires . . . . . . . . . . . . . . . . . . . . . . " 147
Yuma Clapper Rail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 147
Cumulative Effects: Yuma Clapper Rail. . . . . . . . . . . . . . . . . . . . . .. 147
Cumulative effects of human population growth . . . . . . . . . . . " 147
Cumulative effects of economic development . . . . . . . . . . . . . .. 148
Cumulative effects of future visitation/recreation ............ 148
Cumulative effects of environmental contaminants ........... 148
Cumulative effects of wildfires . . . . . . . . . . . . . . . . . . . . . . .. 148
Flat-tailed Horned Lizard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 148
Mortality and Injury of Flat-tailed Horned Lizards
During Operation, and Maintenance of the Roads
and Ancillary Facilities. . . . . . . . . . . . . . . . . . . . . . . . . . . " 148
Cumulative Effects: Flat-tailed Horned Lizard. . . . . . . . . . . . . . . . . " 150

SUMMARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 150

Bony tail Chub and Razorback Sucker . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 150
Southwestern Willow Flycatcher ................................ 151
Yuma Clapper Rail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 151
Flat-tailed Horned Lizard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 151

CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 152
Bony tail Chub and Razorback Sucker .................. . . . . . . . . . " 152
Basis for the Analyses .................................. 152
Bony tail Chub ....................................... 153
Razorback Sucker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 153
Critical Habitat ...................................... 154
Southwestern Willow Flycatcher ................................ 155
Yuma Clapper Rail. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 155