Rocky Intertidal Community Monitoring 2001 Annual Report CHANNEL ISLANDS NATIONAL PARK National Park Service Channel Islands National Park Technical Report Rocky Intertidal Monitoring Channel Islands National Park 2001 Annual Report Daniel V. Richards and Derek Lerma Channel Islands National Park 1901 Spinnaker Drive Ventura, CA 93001 CHIS-2005-08 Rocky Intertidal Monitoring 2001 Annual Report Abstract The 2001 results are presented for the Channel Islands National Park Rocky Intertidal Monitoring Program. This program is part of the long-term ecological monitoring and began in 1982 with four sites at Anacapa Island. Twenty-one permanent sites covering all five park islands were monitored in spring and fall of 2001. This report covers sampling between March 2001 and January 2002. Permanent photoplots were monitored for changes in percent cover of selected indicator organisms. Abundance (density) and size distributions of black abalone, Haliotis cracherodii, were taken in both fixed plots and in timed searches. Owl limpets, Lottia gigantea, density and size distributions were taken within fixed plots. Seastar (generally Pisaster ochraceus) relative abundance was measured in timed searches or fixed transects. Temperature loggers collected hourly temperature data at nine sites. Comprehensive surveys were performed at 15 sites by a team from UCSC/PISCO. No significant trends or anomalies were found in 2001. Cover photo: Derek Lerma and Sean Hastings scoring mussel zone photoplot at East Point Santa Rosa Island, April 2001. Photo by Dan Richards Rocky Intertidal Monitoring 2001 Annual Report TABLE OF CONTENTS Abstract ...............................................................................................................4 TABLE OF CONTENTS .......................................................................................5 LIST OF TABLES.................................................................................................6 LIST OF FIGURES ...............................................................................................6 Executive Summary............................................................................................7 Introduction.......................................................................................................10 Methods .............................................................................................................11 Study Area................................................................................................................... 11 Monitoring............................................................................................................................................11 Results...............................................................................................................14 Photoplots.................................................................................................................... 15 Motile invertebrates ..................................................................................................... 22 Black Abalone (Haliotis cracherodii)............................................................................ 22 Owl Limpets (Lottia gigantea)...................................................................................... 24 Seastars (Pisaster ochraceus) .................................................................................... 30 Surfgrass (Phyllospadix spp.)...................................................................................... 30 Shorebirds and Pinnipeds ........................................................................................... 31 Visitation......................................................................................................................35 Trip Reports................................................................................................................. 36 Species Diversity......................................................................................................... 36 Discussion.........................................................................................................37 Acknowledgments ............................................................................................42 References ........................................................................................................43 Appendix A. Photoquadrat Data.................................................................... A1 Appendix B. Trip Reports…………………………………..……………………..B1 Channel Islands National Park, Tech. Rep. 05-08 5 Rocky Intertidal Monitoring 2001 Annual Report LIST OF TABLES Table 1. 2001 Sampling dates for Rocky Intertidal Monitoring sites ............................... 15 Table 2. Haliotis cracherodii density and sizes pooled by island in 2001. ...................... 23 Table 3. Sea star and black abalone searches in 2001. (-- indicates no plot or transect, nc indicate no count performed, Po= Pisaster ochraceus, Pg=P. giganteus, Am= Asterina miniata, compsurvey= counts made during Comprehensive Surveys)) .... 29 Table 4. Shorebirds and pinnipeds at monitoring sites in spring 2001 (maximum seen at any one time) (*= nearby but not on reef)................................................................ 33 Table 5. Shorebirds and pinnipeds at monitoring sites in fall 2001 (maximum seen at any one time) (*= nearby but not on reef)....................................................................... 34 Table 6. Visitors to South Frenchy’s Cove, Anacapa Island in 2001 (visitation with Island Packers)................................................................................................................... 35 LIST OF FIGURES Figure 1. Rocky Intertidal Community Monitoring Site Locations in Channel Islands National Park ........................................................................................................... 14 Figure 2. Percent cover of target taxa within fixed plots by zone, spring 2001. .............. 19 Figure 3. Percent cover of target taxa within fixed plots by zone, fall 2001. ................... 20 Figure 4. Percent cover of target taxa within fixed plots by zone in 2001 (zones not represented at all sites). .......................................................................................... 21 Figure 5. Owl limpets, Lottia gigantea, at Santa Cruz Island. ........................................ 25 Figure 6. Owl limpets, Lottia gigantea, at Santa Rosa Island. ........................................ 26 Figure 7. Owl limpets, Lottia gigantea at San Miguel Island. .......................................... 27 Figure 8. Owl limpets, Lottia gigantea at Anacapa Island............................................... 28 Figure 10. Visitation at Frenchy’s Cove, Anacapa Island by month. Island Packers visitation figures. ...................................................................................................... 36 Figure 11. 2001 sea temperature anomalies by three month running mean (NOAA Climate Prediction Center website) ......................................................................... 37 Channel Islands National Park, Tech. Rep. 05-08 6 Rocky Intertidal Monitoring 2001 Annual Report Executive Summary The Channel Islands National Park Rocky Intertidal Monitoring Program monitored 21 established sites on the five park islands in 2001. Sites were monitored in spring (March through May) and fall (October through January 2002). Sites were established between 1982 and 1994 and have been monitored regularly since then following established protocols (Richards and Davis 1988). Data show that 2001 was a fairly average year for the most species. Rockweeds, Hesperophycus californicus and Silvetia compressa, mussels, Mytilus californianus, and leaf barnacles, Pollicipes polymerus, were near the long-term mean cover at most sites. Cover of the red alga Endocladia muricata, was fairly dense at many of the sites and the photoplot data support that observation with the mean cover being higher than the long- term mean at most sites. Acorn barnacles, Chthamalus spp. and Balanus glandula, and red thatched barnacles, Tetraclita rubescens, were both slightly below the long-term mean. 2001 was a fairly typical year for weather and sea temperature. The average yearly mean temperature from the all of the Channel Islands National Park Kelp Forest Monitoring Data was 14.5°C. Temperature anomalies reported by the National Oceanographic and Atmospheric Administration were negative during most months in 2001 but slightly positive in the summer months. The Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO)/University of California, Santa Cruz intertidal crew joined us in fall 2001 to conduct biodiversity survey transects at 17 sites on the park islands. The biodiversity surveys analyzed by species lists generated from the transects were found to cluster by water temperature with San Miguel, San Nicolas, Santa Rosa, western Santa Cruz, and South Frenchy’s Cove clustering together in a cold water group. Eastern Santa Cruz, Middle Anacapa, and Santa Barbara Island clustered together in a middle group, and sites at Catalina clustered in their own warm water group. Motile invertebrate counts have been employed to gain a better understanding of the whole intertidal community. From the photoplots we get information about the cover of Channel Islands National Park, Tech. Rep. 05-08 7 Rocky Intertidal Monitoring 2001 Annual Report algae and sessile invertebrates but it