DRAFT ENVIRONMENTAL IMPACT STATEMENT CONTRIBUTIONS FOR PROPOSED SUNZIA TRANSMISSION LINE ROUTES TRAVERSING THE SAN PEDRO RIVER VALLEY SUBMITTED BY THE CASCABEL WORKING GROUP JULY 28, 2010 i AUTHORS NEPA requires that the preparers of the Environmental Impact Statement (EIS) and their qualifications be listed. Daniel Baker is the principal author of this document. Mr. Baker received his Bachelor of Arts degrees in Philosophy and English Literature from Westmont College in Santa Barbara, California before several years of graduate study in Philosophy of Religion. He eschewed doctoral fellowships in philosophy to pursue a career in graphic arts. As a principal partner in a successful business, he served in several administrative and executive capacities before moving to Cascabel in 1994 where he has lived since. He is a major shareholder in the Saguaro Juniper Corporation, and was a founder of the non-profit Cascabel Hermitage Association where he continues to serve on the board of directors as secretary. He served as a Supervisor for the Redington Natural Resource Conservation District (NRCD) for several years and was naMed NRCD Cooperator of the Year in 1996. He was hired by The Nature Conservancy (TNC) and served in the capacity of Cascabel Community Steward until 2002. He was principally involved in TNC’s acquisition of the Three-Links Farm. In his TNC capacity he travelled the length of the San Pedro River from its headwaters in Mexico to its confluence with the Gila River, and helped lead numerous tours of its lower reaches. He facilitated and recently helped complete conservation easements on nearly 2000 acres in Hot Springs Canyon, a major tributary of the San Pedro River. He continues to lead Middle San Pedro River Valley natural history tours for various universities, environmental and church groups, drawing on his education with TNC and as an amateur naturalist. He currently serves as board member and secretary of The Cascabel Working Group, and is a homeowner in Cascabel. Robert Evans compiled and prepared the “Birds of the Lower San Pedro River Valley” bird list and comparative chart (see Appendix). Mr. Evans is a retired electrical engineer, a homeowner in Cascabel, and a board member of the Cascabel Working Group. He is a member of the Colorado Field Ornithologists, Western Field Ornithologists, Rocky Mountain Bird Observatory, National Audubon Society, and the American Birding Association and has travelled extensively throughout the world on birding expeditions. Monica Stephens is responsible for the layout and formatting of this document, and is a member of the Cascabel Working Group. Ms. Stephens received Bachelor of Arts degrees in Geography and International Development from Clark University in Worcester, Massachusetts; a Master’s in Geography from the University of Arizona; and is currently teaching Geographic Information Science and Cartography while pursuing a PhD in Geography at the University of Arizona. She has worked throughout the United States and Canada as a Geographic Consultant for real estate acquisitions. She also assisted her intern, Dietrich Walker, to produce many of the maps of the San Pedro River Valley contained in this document. The Cascabel Working Group board members and members at large were exceedingly helpful in prepararing this document by virtue of their support, comments and literature recommendations. The Redington and Winkelman Natural Resource Conservation Districts were valuable partners with regard to their support and Coordination status with the Bureau of Land Management. The Nature Conservancy and Tucson Audubon contributed valuable resources for the preparation of this document. i TABLE OF CONTENTS AUTHORS ........................................................................................................................................................... i TABLE OF CONTENTS .................................................................................................................................. ii TABLE OF FIGURES ..................................................................................................................................... iv I. INTRODUCTION ........................................................................................................................................ 1 II. GEOGRAPHICAL AREA ......................................................................................................................... 5 III. MIDDLE SPRV – INDIRECT IMPACTS ......................................................................................... 6 A. NEPA – CONTEXT AND INTENSITY ............................................................................................................... 6 B. SPRV GENERAL ATTRIBUTES ........................................................................................................................ 6 1. San Pedro River ....................................................................................................................................... 6 2. Unfragmented and Intact landscape ................................................................................................ 9 3. Historic and Cultural Resources (cursory) ................................................................................... 12 4. Protected Status Lands and Partners ............................................................................................ 14 C. ECOREGIONAL ANALYSES ............................................................................................................................. 17 1. Ecoregional Science ............................................................................................................................... 18 2. Sonoran Desert Ecoregion................................................................................................................... 21 3. Chihuahuan Desert Ecoregion............................................................................................................ 23 4. Madrean Ecoregion................................................................................................................................. 25 5. Arizona Mountains Ecoregion ............................................................................................................. 26 6. Gila Freshwater Ecoregion .................................................................................................................. 27 D. CONNECTIVITY .......................................................................................................................................... 29 E. SUMMARY ....................................................................................................................................................... 35 IV. MIDDLE SPRV – DIRECT IMPACTS......................................................................................... 38 A. NEPA – DIRECT AND CUMULATIVE IMPACTS ............................................................................................. 38 B. LANDSCAPE FRAGMENTATION ...................................................................................................................... 38 1. Edge Effects .............................................................................................................................................. 40 2. Areal Impacts ........................................................................................................................................... 43 ii 3. Erosion ........................................................................................................................................................ 45 4. Off­Road Incursions ............................................................................................................................... 48 C. BIRDS ............................................................................................................................................................. 51 1. Birds of the San Pedro ­ General .................................................................................................... 52 2. Birds of the Lower San Pedro River Valley .................................................................................. 55 3. Declining Avian Populations in Declining Habitats .................................................................... 61 4. Powerline Fragmentation of Avian Aerial Space ........................................................................ 67 5. Summary .................................................................................................................................................. 72 D. WATERS, FISH AND AMPHIBIANS: .............................................................................................................. 73 1. General ...................................................................................................................................................... 74 2. Sedimentation ........................................................................................................................................ 78 3. Intermittent and Ephemeral Waters and Springs ..................................................................... 82 E. MAMMALS ....................................................................................................................................................... 88 F. REPTILES .......................................................................................................................................................