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Sonoma-Mendocino Bull Kelp Recovery Plan Sonoma-Mendocino Bull Kelp Recovery Plan For Greater Farallones National Marine Sanctuary and California Department of Fish & Wildlife April 2019 i Cover photo credits (top left) S. Lonhart, NOAA (top right) A. Maguire, CDFW (bottom) S. Lonhart, NOAA Citation: Hohman, R., Hutto, S., Catton, C. and F. Koe. 2019. Sonoma-Mendocino Bull Kelp Recovery Plan. Plan for the Greater Farallones National Marine Sanctuary and the California Department of Fish and Wildlife. San Francisco, CA. 166 pp. This work was made possible with support from: ii Kelp Recovery Working Group Members Co-Chairs: Francesca Koe, Greater Farallones National Marine Sanctuary Advisory Council (GFNMS AC) Cynthia Catton, California Department of Fish and Wildlife Members: Sara Allen, National Parks Service, GFNMS AC Tom Bell, University of California Santa Barbara Bob Bertelli, California Sea Urchin Commission Mark Carr, University of California Santa Cruz Cyndi Dawson, Ocean Protection Council Barbara Emley, Pacific Coast Federation of Fishermen’s Associations, GFNMS AC Tom Ford, The Bay Foundation Jan Freiwald, Reef Check Mike Graham, Moss Landing Marine Laboratory Frank Hurd, The Nature Conservancy John Largier, Bodega Marine Lab, GFNMS AC Abby Mohan, GFNMS AC Josh Russo, Waterman’s Alliance, GFNMS AC Sheila Semans, Noyo Center for Marine Science Javier Silva, Sherwood Valley Band of Pomo Indians Bibit Traut, City College of San Francisco, GFNMS AC Suki Waters, WaterTreks Ecotours Technical Advisors: Steve Lonhart, Monterey Bay National Marine Sanctuary Rebecca Flores-Miller, California Department of Fish and Wildlife Staff to the Working Group: Sara Hutto, Greater Farallones Association Jenn Gamurot, Greater Farallones Association Rietta Hohman, Greater Farallones Association iii TABLE OF CONTENTS List of Tables List of Figures Executive Summary 1.0 Introduction ................................................................................................................................. 1 2.0 Background ................................................................................................................................. 2 2.1 Description of the study region ...................................................................................... 2 2.2 Upwelling ....................................................................................................................... 4 2.3 Marine Protected Areas .................................................................................................. 5 2.4 Bull Kelp Forests ............................................................................................................ 6 2.4.1 Range .............................................................................................................. 6 2.4.2 Morphology and Reproduction ....................................................................... 7 2.4.3 Ecosystem Services ......................................................................................... 7 2.4.4 Natural Variability and Abundance of Bull Kelp ........................................... 9 2.5 Problem Background .................................................................................................... 10 3.0 Climatic and Ecological Stressors Contributing to Kelp Forest Loss ....................................... 12 3.1 Persistent Marine Heatwaves ........................................................................................ 13 3.2 Sea Star Wasting Syndrome ......................................................................................... 15 3.3 Purple Sea Urchin Population Increase ........................................................................ 16 3.4 Sea Otter Extirpation .................................................................................................... 18 3.5 Harmful Algal Blooms ................................................................................................. 19 3.6 Anthropogenic Stressors .............................................................................................. 20 4.0 Economic and Cultural Impacts of Kelp Forest Loss ............................................................... 20 5.0 Kelp Recovery Working Group ................................................................................................ 22 5.1 Purpose Statement, Goals and Scope ........................................................................... 22 5.2 Working Group Process and Timeline ......................................................................... 23 6.0 Strategies for Active Kelp Recovery ......................................................................................... 24 6.1 Reduce Grazing Pressure .............................................................................................. 26 6.2 Enhance Kelp ................................................................................................................ 31 7.0 Restoration Site Selection ......................................................................................................... 32 7.1 Strategies to Identify Candidate Regions and Sites for Restoration ............................. 32 7.2 Guidelines for Applying Site Selection Criteria ........................................................... 33 7.3 Methods ........................................................................................................................ 39 iv 7.4 Site Selection Analysis ................................................................................................. 40 7.5 Recommended Priority Regions for Recovery Action ................................................. 82 8.0 Strategies for Monitoring and Research .................................................................................... 84 8.1 Techniques and Limitations .......................................................................................... 85 8.2 Case Studies and Current Research .............................................................................. 89 9.0 Strategies for Community Engagement .................................................................................... 93 9.1 Guidelines to Develop Consistent Messaging and Engage Audiences ......................... 94 9.1.1 Ongoing Community Engagement Efforts .................................................... 98 9.1.2 Opportunities for Public Involvement in Citizen Science ........................... 100 10.0 Integration with Relevant Action Plans .................................................................................. 101 11.0 Conclusion and Next Steps ..................................................................................................... 104 11.1 Establish a Kelp Recovery Project and Network ........................................................ 104 11.1.1 Build on Existing Partnerships .................................................................... 104 11.2 Implement the Strategies ............................................................................................ 105 12.0 References ............................................................................................................................... 107 Appendix A: Working Group Membership ...................................................................................... 115 Appendix B: Working Group Meeting Summaries .......................................................................... 117 Appendix C: Established Partnerships .............................................................................................. 127 Appendix D: Site Selection Criteria Rankings ................................................................................. 128 v List of Tables Table 1. Ecosystem services and functions provided by bull kelp forests (Springer et al. 2010) .............. 10 Table 2. Summary of commercial urchin harvest efforts in 2018 in the AOI. ........................................... 28 Table 3. Descriptions, reasoning and categories for site selection criteria considered by the Working Group. ......................................................................................................................................... 36 Table 4. Rankings used to determine recommendations for priority regions and sites based on selection criteria. ....................................................................................................................................................... 79 Table 5. Sites of economic value to the recreational abalone harvest. Economic value is derived by the reduction per trip in dollars predicted by Reid et al. that would be lost due to the closure of the recreational abalone fishery (2016). .............................................................................................................................. 81 List of Figures Figure 1. Area of Interest (AOI) for the Recovery Plan is the nearshore habitat of Sonoma and Mendocino counties suitable for bull kelp forests (blue line), and area of the coastline that is 206 miles (331 kilometers) long. ..................................................................................................................................... 3 Figure 2. Upwelling is the process by which surface waters are pushed away from the coastline by surface winds and are replaced by cold, nutrient-rich water that wells up from the bottom of the ocean (NOAA). Upwelling is critical for kelp recruitment and growth. ...............................................................................
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