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Rocky Intertidal Community Monitoring at Channel Islands National Park 2009 Annual Report

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Rocky Intertidal Community Monitoring at Channel Islands National Park 2009 Annual Report National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Rocky Intertidal Community Monitoring at Channel Islands National Park 2009 Annual Report Natural Resource Data Series NPS/CHIS/NRDS—2012/372 ON THE COVER Ochre seastars feeding on mussels at East Point, Santa Rosa Island Photograph by: Dan Richards Rocky Intertidal Community Monitoring at Channel Islands National Park 2009 Annual Report Natural Resource Data Series NPS/CHIS/NRDS—2012/372 Daniel V. Richards Stephen G. Whitaker National Park Service Channel Islands National Park 1901 Spinnaker Drive Ventura, CA 93001 September 2012 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are 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 Data Series is intended for timely release of basic data sets and data summaries. Care has been taken to assure accuracy of raw data values, but a thorough analysis and interpretation of the data has not been completed. Consequently, the initial analyses of data in this report are provisional and subject to change. This report received informal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data. Data in this report were collected and analyzed using methods based on established, peer-reviewed protocols and were analyzed and interpreted within the guidelines of the protocols. 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 also available from the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/) or the Mediterranean Coast Network (http://science.nature.nps.gov/im/units/medn/) on the Internet. Please cite this publication as: Richards, D. V., and S. G. Whitaker. 2012. Rocky intertidal community monitoring at Channel Islands National Park: 2009 annual report. Natural Resource Data Series NPS/CHIS/NRDS— 2012/372. National Park Service, Fort Collins, Colorado. NPS 159/117130, September 2012 ii Contents Page Figures............................................................................................................................................. v Tables ............................................................................................................................................ vii Executive Summary ....................................................................................................................... ix Acknowledgments.......................................................................................................................... xi List of Acronyms ......................................................................................................................... xiii Introduction: .................................................................................................................................... 1 Methods........................................................................................................................................... 3 Study Area ............................................................................................................................... 3 Monitoring ............................................................................................................................... 5 Data Analysis ......................................................................................................................... 10 Results ........................................................................................................................................... 12 2009 Sampling Events ........................................................................................................... 12 Photoplots .............................................................................................................................. 13 Motile Invertebrates ............................................................................................................... 18 Haliotis cracherodii ............................................................................................................... 21 Lottia gigantea ....................................................................................................................... 22 Pisaster ochraceus ................................................................................................................. 30 Phyllospadix spp. ................................................................................................................... 32 Shorebirds and Pinnipeds ...................................................................................................... 35 Visitation ................................................................................................................................ 40 Trip Reports ........................................................................................................................... 42 Discussion ..................................................................................................................................... 43 Literature Cited ............................................................................................................................. 51 Appendix A: Program Notes ....................................................................................................... A-1 Appendix B. Photoquadrat Data Tables..................................................................................... B-1 iii Contents (continued) Page Appendix C. Trip Reports ........................................................................................................... C-1 Appendix D. Motile Invertebrates………………………………………....................................D-1 iv Figures Page Figure 1. Rocky Intertidal Community Monitoring Site Locations in Channel Islands National Park .................................................................................................................................. 1 Figure 2. Stephen Whitaker scoring photoplots at Trailer, Santa Cruz Island. .............................. 7 Figure 3. Stephen Whitaker counting motile invertebrates at East Point with volunteer, Connie Jenkins, recording. .............................................................................................................. 8 Figure 4. Percent cover of target species (Chthamalus/Balanus, Endocladia muricata, Silvetia compressa, and Mytilus californianus) in fixed plots by zone in spring 2009 ................ 15 Figure 5. Percent cover of target species (Chthamalus/Balanus, Endocladia muricata, Silvetia compressa, and Mytilus californianus) in fixed plots by zone in fall 2009 ..................... 16 Figure 6. Percent cover of target taxa (Red algal turf, Tar, Tetraclita rubescens, Pollicipes polymerus, and Hesperophycus californicus) in fixed plots by zone in 2009 ............. 17 Figure 7. Species mean abundances for 2009 at each site ............................................................ 19 Figure 8. Haliotis cracherodii density estimates at all islands except Santa Cruz from 1985-1999 ..................................................................................................................................... 24 Figure 9. Haliotis cracherodii counts at all islands from 2000-2009 ........................................... 24 Figure 10. Haliotis cracherodii size distributions in spring 2009 ................................................ 21 Figure 11. Haliotis cracherodii size distributions in fall 2009 ..................................................... 22 Figure 12. Lottia gigantea size distributions in spring 2009 ........................................................ 24 Figure 13. Lottia gigantea size distributions in fall 2009. ............................................................ 25 Figure 14. Lottia gigantea at Anacapa Island 1999-2009............................................................ 26 Figure 15. Lottia gigantea at Santa Cruz Island 1998-2009 ......................................................... 27 Figure 16. Lottia gigantea at Santa Rosa Island 1998-2009. ........................................................ 28 Figure 17. Lottia gigantea at San Miguel Island 2001-2009 ........................................................ 29 Figure 18. Pisaster ochraceus sampled in spring 2009 ................................................................ 31 v Figures (continued) Page Figure 19. Pisaster ochraceus sampled in fall 2009 ..................................................................... 31 Figure 20. Surfgrass, Phyllospadix spp., cover trends on 10m point-intercept transects at Fraser Cove and Trailer on Santa Cruz Island and East Point and Northwest-Talcott on Santa Rosa Island .........................................................................................................................
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