Carnivore Activity and Movement in a Southern California Protected Area, the North/Central Irvine Ranch 2006 Prepared for: The Nature Conservancy U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY WESTERN ECOLOGICAL RESEARCH CENTER Carnivore Activity and Movement in a Southern California Protected Area, the North/Central Irvine Ranch By Lisa M. Lyren1, Greta M. Turschak2, Erick S. Ambat2, Chris D. Haas 2, Jeff A. Tracey3, Erin E. Boydston4, Stacie A. Hathaway2, Robert N. Fisher 2, and Kevin R. Crooks3 U.S. GEOLOGICAL SURVEY WESTERN ECOLOGICAL RESEARCH CENTER COLORADO STATE UNIVERSITY 2006 Prepared for: The Nature Conservancy Trish Smith 1400 Quail Street, Ste 130 Newport Beach, CA 92660 U.S. Geological Survey - BRD Western Ecological Research Center 1Carlsbad Office 6010 Hidden Valley Road Carlsbad, CA 92009 2San Diego Field Station 5745 Kearny Villa Road, Suite M San Diego, CA 92123 4Irvine Office 320 Commerce, Suite 150 Irvine, CA 92602 3Colorado State University Department of Fish, Wildlife, and Conservation Biology Ft. Collins, CO 80523 Sacramento, California 2006 ii U.S. DEPARTMENT OF THE INTERIOR GALE A. NORTON, SECRETARY U.S. GEOLOGICAL SURVEY P. Patrick Leahy, Acting Director The use of firm, trade, or brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. For additional information, contact: Center Director Western Ecological Research Center U.S. Geological Survey 3020 State University Drive East Modoc Hall, Room 3006 Sacramento, CA 95819 iii TABLE OF CONTENTS ABSTRACT.................................................................................................................................1 INTRODUCTION .......................................................................................................................2 OBJECTIVES..............................................................................................................................4 METHODS ..................................................................................................................................4 Study Area.......................................................................................................................4 Track and Camera Surveys ..............................................................................................5 GPS Radio Collars...........................................................................................................6 Bobcats.............................................................................................................................7 Mountain Lions................................................................................................................10 Home Range Analyses.....................................................................................................12 Analyses of Movements across Roads.............................................................................12 RESULTS ....................................................................................................................................13 Track and Camera Surveys ..............................................................................................13 Bobcats.............................................................................................................................15 Mountain Lions................................................................................................................17 Road Encounter Densities for Proposed Jamboree Road Extension ...............................20 DISCUSSION..............................................................................................................................20 CONSIDERATIONS FOR LONG-TERM MONITORING: Methods.......................................23 CONSIDERATIONS FOR LONG-TERM MONITORING: Other Factors...............................26 SUMMARY OF MONITORING RECOMMENDATIONS ......................................................28 ROADWAY MITIGATION........................................................................................................29 SUMMARY OF ROADWAY MITIGATION RECOMMENDATIONS ..................................31 ACKNOWLEDGEMENTS.........................................................................................................32 LITERATURE CITED ................................................................................................................33 NIR Carnivore Movement iv U.S. Geological Survey and Colorado State University The Nature Conservancy 2006 LIST OF TABLES Table 1. GPS coordinates of CA-241and Santiago Canyon Road undercrossings..................43 Table 2. GPS coordinates of track transects and camera station locations..............................44 Table 3. GPS Posrec-120™ radio-collar programming schedules for bobcats .......................45 Table 4. GPS coordinates of Phase 1 bobcat trapping locations..............................................46 Table 5. GPS coordinates of Phase 2 bobcat trapping locations..............................................47 Table 6. GPS coordinates for mountain lion trapping locations..............................................48 Table 7. Total sampling effort for track transects and camera stations ...................................49 Table 8. Mammal species detected at track transects ..............................................................50 Table 9. Mammal species detected at camera stations on possible Jamboree Rd extension ...51 Table 10. Mammal species detected at camera stations along North Lake Rd..........................52 Table 11. Capture and monitoring data for 12 bobcats from Phase 1........................................53 Table 12. Capture and monitoring data for eight bobcats from Phase 2....................................54 Table 13. GPS location data and home range estimates for all radio-collared bobcats.............55 Table 14. Location and frequency of road crossings by B6.......................................................56 Table 15. Location and frequency of road crossings by B10.....................................................57 Table 16. Location and frequency of road crossings by B13.....................................................58 Table 17. Capture and monitoring data for three mountain lions ..............................................59 Table 18. GPS location data and home range estimates for all radio-collared mountain lions .59 Table 19. Location and frequency of road crossings by P1.......................................................60 Table 20. Location and frequency of road crossings by P2.......................................................61 Table 21. Location and frequency of road crossings by P3.......................................................62 LIST OF FIGURES Figure 1a. Map of study area.......................................................................................................63 Figure 1b. Map of CA-241 and Santiago Canyon Road undercrossings, and a proposed Jamboree Road extension .........................................................................................64 Figure 2. Map of track transects................................................................................................65 Figure 3. Map of camera stations ..............................................................................................66 Figure 4. Map of track transects and camera station locations .................................................67 Figure 5. Map of bobcat trap locations Phase 1 ........................................................................68 Figure 6. Map of bobcat trap locations Phase 2 ........................................................................69 Figure 7. Map of mountain lion trap locations..........................................................................70 Figure 8. Map of all bobcat and mountain lion trap locations ..................................................71 Figure 9. GPS Simplex™ radio-collar programming schedules for mountain lions ................72 Figure 10. Seasonal monitoring schedule for radio-collared bobcats and mountain lions..........73 Figure 11. All Phase 1 and 2 GPS locations for 16 bobcats........................................................74 Figure 12. Area-observation curves using the 100% MCP for male radio-collared bobcats......75 Figure 13. Area-observation curves using the 100% MCP for B6 and B13 ...............................76 Figure 14. Area-observation curves using the 100% MCP for female radio-collared bobcats...77 Figure 15. GPS locations, movement paths, and home ranges for B2........................................78 Figure 16. GPS locations, movement paths, and home ranges for B4........................................79 Figure 17. GPS locations, movement paths, and home ranges for B5........................................80 Figure 18. GPS locations, movement paths, and home ranges for B6........................................81 Figure 19. GPS locations, movement paths, and home ranges for B7........................................82 NIR Carnivore Movement v U.S. Geological Survey and Colorado State University The Nature Conservancy 2006 Figure 20. GPS locations, movement paths, and home ranges for B8........................................83 Figure 21. GPS locations, movement paths, and home ranges for B9........................................84 Figure 22. GPS locations, movement paths, and home ranges for B10......................................85