South Coast Missing Linkages Project: A Linkage Design for the PalomarPalomar----SanSan Jacinto/Santa Rosa Connection Prepared by: Kristeen Penrod Clint Cabañero Dr. Paul Beier Dr. Claudia Luke Dr. Wayne Spencer Dr. Esther Rubin South Coast Missing Linkages ProjectProject:::: A Linkage Design for the PalomarPalomar----SanSan JacintoJacinto/Santa/Santa Rosa Connection Prepared by: Kristeen Penrod Clint R. Cabañero Dr. Paul Beier Dr. Claudia Luke Dr. Wayne Spencer Dr. Esther Rubin May 2006 This report was made possible with financial support from the Resources Legacy Fund Foundation, The Wildlands Conservancy, The Resources Agency, California State Parks, U.S. Forest Service, California State Parks Foundation, Anza Borrego Foundation, Environment Now, Zoological Society of San Diego, and the Summerlee Foundation. Produced by South Coast Wildlands: Our mission is to protect, connect and restore the rich natural heritage of the South Coast Ecoregion through the establishmeestablishmentnt of a system of connected wildlands. Preferred Citation: Penrod, K., C. Cabañero, P. Beier, C. Luke, W. Spencer, and E. Rubin. 2006. South Coast Missing Linkages Project: A Linkage Design for the Palomar-San Jacinto/Santa Rosa Connection. South Coast Wildlands, Idyllwild, CA. www.scwildlands.org. II Project Partners: We would like to recognize our partners on the South Coast Missing Linkages Project, including The Wildlands Conservancy, The Resources Agency, U.S. Forest Service, California State Parks, California State Parks Foundation, National Park Service, San Diego State University Field Stations Program, Environment Now, The Nature Conservancy, Conservation Biology Institute, Santa Monica Mountains Conservancy, Wetlands Recovery Project, Mountain Lion Foundation, Rivers and Mountains Conservancy, California Wilderness Coalition, Anza Borrego Foundation, Zoological Society of San Diego Center for Reproduction of Endangered Species, Pronatura, Conabio, and Universidad Autonoma de Baja California. We are committed to collaboration to secure a wildlands network for the South Coast Ecoregion and beyond and look forward to adding additional agencies and organizations to our list of partners. III Table of Contents List of Tables & Figures VI Acknowledgements VIII Executive Summary IX Introduction Nature Needs Room to Roam 1 Patterns of Habitat Conversion 1 A Statewide Vision 2 South Coast Missing Linkages: A Vision for the Ecoregion 2 Ecological Significance of the Palomar-San Jacinto/Santa Rosa Connection 4 Existing Conservation Investments 5 Conservation PlanPlanningning Approach Preface 7 Focal Species Selection 8 Landscape Permeability Analysis 8 Patch Size & Configuration Analysis 12 Minimum Linkage Width 14 Field Investigations 14 Identify Conservation Opportunities 14 Landscape Permeability Analyses Landscape Permeability Analyses Summary 16 Mountain lion 17 American badger 18 Mule deer 19 Patch Size & Configuration Analyses Patch Size & Configuration Analyses Summary 20 Mountain ion 22 American badger 24 Mule deer 26 Large-eared woodrat 28 Aguanga kangaroo rat 30 California spotted owl 32 California quail 34 Loggerhead shrike 36 Wrentit 38 Rock wren 40 Chaparral whipsnake 42 Coast horned lizard 44 Western pond turtle 46 Western toad 49 Pale swallowtail 51 IV Quino checkerspot butterfly 52 Our Lord’s candle 56 Linkage Design Goals of the Linkage Design 57 Description of the Linkage 58 Removing and Mitigating Barriers to Movement 64 Roads as Barriers to Upland Movement 64 Roads in the Linkage Design 65 Types of Mitigation for Roads 65 Recommended Crossing Structures on Highway 79 67 Recommended Crossing Structures on Highway 371 71 Recommended Crossing Structures on Highway 74 73 Other Recommendations Regarding Paved Roads within the Linkage Design 76 Roads as Ephemeral Barriers 77 Impediments to Streams 77 Impediments to Streams in the Linkage Design 78 Examples of Mitigation for Stream Barriers 79 Recommendations to Mitigate the Effects of Stream Barriers in the Linkage Design 79 Other Land Uses that Impede Utility of the Linkage 81 Urban Barriers to Movement 81 Urban Barriers in the Linkage Design Area 81 Examples of Mitigation for Urban Barriers 81 Recommendations for Mitigating the Effects of Urbanization in the Linkage Design Area 81 Recreation 82 Recreation in the Linkage Design Area 82 Recommendations for Mitigating the Effects of Recreation in the Linkage Design Area 83 Land Protection & Stewardship Opportunities 83 Summary 93 Literature Cited 95 Appendices (Enclosed CD) A. Workshop Participants B. Workshop Summary C. 3D Visualization of the Palomar-San Jacinto/Santa Rosa Connection V List of Tables Table 1. Focal Species Selected Table 2. Focal Species Movement Criteria Table 3. Vegetation and Land Cover in the Linkage Table 4. Major Transportation Routes in the Linkage Design List of Figures Figure 1. South Coast Ecoregion Figure 2. South Coast Missing Linkages Figure 3. Vegetation Types in the Linkage Planning Area Figure 4. Existing Conservation Investments in the Linkage Planning Area Figure 5. Interdisciplinary Approach Figure 6. Permeability Model Inputs Figure 7. Patch Size & Configuration Model Inputs Figure 8. Least Cost Union Displaying Species Overlap Figure 9. Least Cost Union Figure 10. Least Cost Corridor for Mountain lion Figure 11. Least Cost Corridor for American badger Figure 12. Least Cost Corridor for Mule deer Figure 13. Least Cost Union Additions Figure 14. Habitat Suitability for Mountain lion Figure 15. Potential Cores & Patches for Mountain lion Figure 16. Habitat Suitability for American badger Figure 17. Potential Cores & Patches for American badger Figure 18. Habitat Suitability for Mule deer Figure 19. Potential Cores & Patches for Mule deer Figure 20. Habitat Suitability for Large-eared woodrat Figure 21. Potential Cores & Patches for Large-eared woodrat Figure 22. Patch Configuration for Large-eared woodrat Figure 23. Habitat Suitability for Aguanga kangaroo rat Figure 24. Potential Cores & Patches for Aguanga kangaroo rat Figure 25. Habitat Suitability for California spotted owl Figure 26. Potential Cores & Patches for California spotted owl Figure 27. Habitat Suitability for California quail Figure 28. Potential Cores & Patches for California quail Figure 29. Habitat Suitability for Loggerhead shrike Figure 30. Potential Cores & Patches for Loggerhead shrike Figure 31. Habitat Suitability for Wrentit Figure 32. Potential Cores & Patches for Wrentit Figure 33. Habitat Suitability for Rock wren Figure 34. Potential Cores & Patches for Rock wren Figure 35. Habitat Suitability for Chaparral whipsnake Figure 36. Potential Cores & Patches for Chaparral whipsnake Figure 37. Habitat Suitability for Coast horned lizard Figure 38. Potential Cores & Patches for Coast horned lizard Figure 39. Patch Configuration for Coast horned lizard Figure 40. Potential habitat for Western pond turtle Figure 41. Potential habitat for Western toad Figure 42. Potential habitat for Pale swallowtail Figure 43. Potential habitat for Quino checkerspot butterfly VI Figure 44. Potential habitat for Our Lord’s candle Figure 45. Linkage Design Figure 46. Northern branch of the linkage Figure 47. Central branch of the linkage Figure 48. Southern branch of the linkage Figure 49. Existing Infrastructure in the Planning Area Figure 50. An example of a vegetated land bridge built to enhance movement of wildlife populations. Figure 51. A viaduct in Slovenia built to accommodate wildlife, hydrology, and human connectivity. Figure 52. Arched culvert on German highway, with rail for amphibians and fence for larger animals Figure 53. Pipe culvert designed to accommodate small mammals Figure 54. Amphibian tunnels allow light and moisture into the structure Figure 55. Arroyo Seco Bridge on Highway 79 Figure 56. Temecula Creek Bridge on Highway 79 Figure 57. Looking up Temecula Creek Figure 58. Looking down Temecula Creek towards Vail Lake Figure 59. Pipe culvert near the juncture of Highways 371/79 Figure 60. Looking up Tule Creek Figure 61. Looking down Chihuahua Creek towards the Palomar Ranges Figure 62. Disturbed area under Highway 371 bridge on Cahuilla Creek Figure 63. View of Cahuilla Creek north of the highway Figure 64. View of Cahuilla Creek south of the highway Figure 65. Culvert for an unnamed drainage on Highway 371 Figure 66. Looking down Hamilton Creek Figure 67. Example of concrete box culvert on Highway 74 in Garner Valley Figure 68. Example of double concrete box culvert on Highway 74 in Garner Valley Figure 69. Looking east toward Palm View Peak Figure 70. Bridge over Antsell Rock Creek on Highway 74 Figure 71. Bridge over Servo Creek on Highway 74 Figure 72. Bridge over Hurkey Creek on Highway 74 Figure 73. Fence obstructing wildlife passage on Hurkey Creek VII Project Steering Committee: We are extremely grateful to the following individuals, who serve on the steering committee for the South Coast Missing Linkages Project: Paul Beier (Northern Arizona University), Madelyn Glickfeld (formerly with The Resources Agency California Legacy Project), Gail Presley (California Department of Fish and Game), Therese O’Rourke (U.S. Fish & Wildlife Service, formerly with The Nature Conservancy), Kristeen Penrod (South Coast Wildlands), Rick Rayburn (California State Parks), Ray Sauvajot (National Park Service), and Tom White (U.S. Forest Service). VIII Executive Summary Habitat loss and fragmentation are the leading threats to biodiversity, both globally and in southern California. Efforts to combat these threats must focus on conserving