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Draft Snake Headwaters Subbasin Summary

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Draft Snake Headwaters Subbasin Summary Draft Snake Headwaters Subbasin Summary May 17, 2002 Prepared for the Northwest Power Planning Council Subbasin Team Leader Edward Bottum, Idaho Department of Fish and Game Lead Writers Patricia A. Isaeff, TREC, Inc. Timothy D. Reynolds, TREC, Inc. Editor Randall C. Morris, TREC, Inc. Primary Contributors (in alphabetical order): Eric Cole, National Elk Refuge Jeffrey Pettingill, Bonneville County Vegetation Kerry Grande, Jackson National Fish Hatchery Management Sheryl Hill, Idaho Department of Environmental Quality Allen Redder, Wyoming Natural Diversity Database Marv Hoyt, Greater Yellowstone Coalition Steve Rust, Idaho Department of Fish and Game Chris Jansen-Lute, Bureau of Reclamation Troy Saffle, Idaho Department of Environmental Quality Howard Johnson, Safari Club International Robert Schiller, Grand Teton National Park Don Kemner, Idaho Department of Fish and Game Ruth Shea, The Trumpeter Swan Society Justin W. Krajewski, Idaho Soil Conservation Commission Bruce Smith, National Elk Refuge Jeff McCreary, Ducks Unlimited Steve Smith, Idaho Soil Conservation Commission Deb Migonono, US Fish and Wildlife Service Kathy Weaver, Idaho Soil Conservation Commission Susan O’Ney, Grand Teton National Park Michael Whitfield, Teton Regional Land Trust Marty Orwig, N. American Moose Foundation DRAFT: This document has not yet been reviewed or approved by the Northwest Power Planning Council Snake Headwaters Subbasin Summary Table of Contents Background & Introduction ............................................................................................................... 1 Subbasin Description ......................................................................................................................... 2 General ....................................................................................................................................... 2 Location...................................................................................................................................... 3 Drainage Area ............................................................................................................................ 5 Topography/ Geomorphology.................................................................................................. 10 Climate ..................................................................................................................................... 14 Hydrology ................................................................................................................................ 18 Water Quality........................................................................................................................... 33 Vegetation ................................................................................................................................ 51 Major Land Uses ...................................................................................................................... 65 Impoundments and Irrigation................................................................................................... 73 Protected Areas ........................................................................................................................ 92 Demographics .......................................................................................................................... 99 Economy and Employment .................................................................................................... 100 Fish and Wildlife Resources .......................................................................................................... 103 Fish and Wildlife Status ......................................................................................................... 103 Wildlife .................................................................................................................................. 126 Threatened and Endangered and Rare Species....................................................................... 126 Mammals: Game, Forest Carnivores, Small Mammals......................................................... 138 Habitat Areas and Quality...................................................................................................... 159 Watershed & Related Assessment.......................................................................................... 162 Assessments Within the Headwaters Subbasin...................................................................... 175 Major Limiting Factors .......................................................................................................... 182 Artificial Fish Production....................................................................................................... 187 Existing and Past Conservation Efforts.................................................................................. 189 Subbasin Management ................................................................................................................... 206 Existing Plans, Polices and Guidelines .................................................................................. 206 Goals, Objectives, Strategies and Recommended Actions..................................................... 221 Research, Monitoring and Evaluation Activities ................................................................... 273 Statement of Fish and Wildlife Needs.................................................................................... 287 Headwaters Subbasin Summary ii DRAFT May 17, 2002 Upper Snake Headwaters Subbasin Recommendations................................................................. 295 Projects and Budgets .............................................................................................................. 295 Research, Monitoring and Evaluation Activities ................................................................... 300 Needed Future Actions........................................................................................................... 310 Actions by Others................................................................................................................... 317 References...................................................................................................................................... 329 Acronyms and Abbreviations......................................................................................................... 340 Appendix A. Surface Water Quality Data Retrievals Appendix B. Sensitive, Threatened, and Endangered Species Inventory & Monitoring Appendix C. Cutthroat Trout Distribution Surveys Appendix D. Species of Concern Appendix E. Southern Idaho Gamebird Research Group, 10 Year Summary Appendix F. Grays Lake National Wildlife Refuge Appendix G. Bird Checklists of the United States: National Elk Refuge Appendix H. Bird Checklists of the United States: Birds of Jackson Hole Appendix I. Idaho Falls Bureau of Land Management District Appendix J. Fish Stocking in Idaho Stream Segments of Headwaters Appendix K. Agencies Contacted Regarding Development of Headwaters Subbasin Summary Headwaters Subbasin Summary iii DRAFT May 17, 2002 Table of Figures Figure 1. Columbia River Basin with major provinces........................................................ 1 Figure 2. Upper Snake Subregion including the Upper Snake Subbasin............................. 4 Figure 3. Snake Headwaters Subbasin originates in Grand Teton National Park, WY. ...... 5 Figure 4. Geology of the Headwaters Subbasin. ................................................................ 11 Figure 5. Koppen Climate Classification throughout the Headwaters Subbasin. .............. 16 Figure 6. Dams and BOR gaging stations in the Upper Snake River Basin (Idaho and Wyoming) as of 9/20/2001.......................................................................................... 18 Figure 7. Current year (2001), previous year (2000) and average monthly streamflow at the BOR Flagg Ranch Gage Station above Jackson Reservoir. .................................. 19 Figure 8. Current year (2001), previous year (2000) and average monthly streamflow at the BOR Snake River Gage Station below Jackson Lake near Moran Junction, WY.20 Figure 9. Current year (2001), previous year (2000) and average monthly streamflow at the BOR Snake River Gage Station below the confluence of Flat Creek near Jackson, WY. ............................................................................................................................. 21 Figure 10. Current year (2001), previous year (2000) and average monthly streamflow at the BOR Snake River Gage Station above the Palisades Reservoir near Alpine, WY. ..................................................................................................................................... 22 Figure 11. Current year (2001), previous year (2000) and average streamflow at the BOR Gage Station in the Salt River near Etna, WY. ........................................................... 23 Figure 12. Current year (2001), previous year (2000), and average monthly streamflow at the BOR Gage Station in the Greys River above Palisades Reservoir near Alpine, WY. ............................................................................................................................. 24 Figure 13. Current year (2001), previous year (2000) and average monthly streamflow at the BOR South Fork Gage Station near Irwin, ID, below Palisades
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