National Park Service U.S. Department of the Interior Natural Resource Program Center San Francisco Bay Area Network Northern Spotted Owl Monitoring Protocol Version 6.4 Natural Resource Report NPS/SFAN/NRR—2010/245 ON THE COVER Female northern spotted owl and fledglings in Point Reyes National Seashore, 2007. Photo by Heather Jensen, NPS. San Francisco Bay Area Network Northern Spotted Owl Monitoring Protocol Version 6.4 Natural Resource Report NPS/SFAN/NRR—2010/245 Press, David Adams, Dawn Jensen, Heather Fehring, Katie1 Merkle, William W.2 Koenen, Marcus Starcevich, Leigh Ann3 National Park Service San Francisco Bay Area I&M Network Point Reyes National Seashore One Bear Valley Road Point Reyes Station, California 94956 1 PRBO Conservation Science 4990 Shoreline Highway Stinson Beach, California 94970 2 Golden Gate National Recreation Area Bldg 201, Fort Mason San Francisco, California 94123 3 University of Idaho PO Box 1032 Corvallis, Oregon 97339 September 2010 U.S. Department of the Interior National Park Service Natural Resource Program Center Fort Collins, Colorado The National Park Service, Natural Resource Program Center publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. This report received formal, high-level peer review based on the importance of its content, or its potentially controversial or precedent-setting nature. Peer review was conducted by highly qualified individuals with subject area technical expertise and was overseen by a peer review manager. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Government. This report is available from the San Francisco Area Network Inventory and Monitoring website (http://science.nature.nps.gov/im/units/sfan) and the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/NRPM). Please cite this publication as: Press, D., D. Adams, H. Jensen, K. Fehring, W. Merkle, M. Koenen, and L. A. Starcevich. 2010. San Francisco Bay Area Network northern spotted owl monitoring protocol : Version 6.4. Natural Resource Report NPS/SFAN/NRR—2010/245. National Park Service, Fort Collins, Colorado. NPS 963/105610, September 2010 ii Revision History Log Prev. Version # Revision Date Author Changes Made Reason for New Change Version # September D. Adams, First draft of Preparation for first 1.0 2003 K. Fehring, monitoring protocol peer review. D. Hatch, S. Allen 1.0 August 2004 D. Adams, Minor revisions to Preparation for first 2.0 K. Fehring, previous version. peer review. B. Merkle 2.0 August 2004 D. Adams, Minor revisions to Preparation for first 3.0 K. Fehring, previous version. peer review. B. Merkle 3.0 September D. Adams, Minor revisions to Preparation for first 4.0 2004 K. Fehring, previous version. peer review. B. Merkle 4.0 October 2004 D. Adams, Minor revisions to Preparation for first 5.0 K. Fehring, previous version. peer review. B. Merkle 5.0 May 2008 D. Adams, Report format edits. To address peer 6.3 H. Jensen, Expanded and review comments K. Fehring, improved sections on and meet current B. Merkle, D. monitoring history, formatting Press, M. previous research, guidelines. Koenen barred owls, and reporting methods. Revised monitoring objectives. Added randomized study design based on new power analyses developed by SFSU. 6.3 April 2010 D. Press, D. Report format edits. To address peer 6.4 Adams, H. Expanded NSO review comments Jensen, K. background info. and meet current Fehring, B. Revised monitoring formatting Merkle, M. objectives. Added guidelines. Koenen, L. management triggers. Starcevich New power analyses and sampling design recommendations from University of Idaho. Added documentation of SOD. Provided details on methods for long-term analyses. iii Contents Page Figures.......................................................................................................................................... viii Tables ............................................................................................................................................. ix Standard Operating Procedures (SOPs) ...........................................................................................x Appendices .......................................................................................................................................x Executive Summary ....................................................................................................................... xi Acknowledgements ...................................................................................................................... xiii 1.0 Background and Objectives .......................................................................................................1 1.1 Northern Spotted Owl Range-wide Status and Habitat Associations ............................... 1 1.2 History of Spotted Owl Monitoring in Marin County ...................................................... 4 1.2.1 NSO Inventory ........................................................................................................ 4 1.2.2 NSO Long-Term Monitoring .................................................................................. 4 1.3 History of Spotted Owl Research in Marin County .......................................................... 6 1.3.1 Habitat Associations ............................................................................................... 7 1.3.2 Nest Structures ........................................................................................................ 8 1.3.3 NSO Prey ................................................................................................................ 8 1.4 Conservation Threats ........................................................................................................ 8 1.4.1 Barred Owls ............................................................................................................ 9 1.4.2 Sudden Oak Death .................................................................................................. 9 1.4.3 Genetic Isolation ................................................................................................... 10 1.4.4 Predation ............................................................................................................... 10 1.5 Measurable Monitoring Objectives ................................................................................. 10 1.6 Management Objectives .................................................................................................. 11 v 1.7 Triggers for Management Activities ............................................................................... 12 2.0 Sampling Design ......................................................................................................................13 2.1 Study Area and Site Selection ......................................................................................... 13 2.2 Sample Design Power Analysis ...................................................................................... 14 2.2.1 Occupancy Analysis.............................................................................................. 15 2.2.2 Fecundity Analysis................................................................................................ 16 2.2.3 Power Analysis ..................................................................................................... 16 2.3 NSO Monitoring Design ................................................................................................. 17 2.3.1 Sampling Frequency and Timing .......................................................................... 18 2.4 Sample Design Review ................................................................................................... 20 2.5 Additional Surveys .......................................................................................................... 20 3.0 Field Methods ..........................................................................................................................21 3.1 Field Season Preparations ............................................................................................... 21 3.2 Sequence of Events during Field Season ........................................................................ 21 3.3 Survey Protocols ............................................................................................................. 21 3.3.1 Activity Center Monitoring..................................................................................