The University of San Francisco USF Scholarship: a digital repository @ Gleeson Library | Geschke Center Master's Projects and Capstones Theses, Dissertations, Capstones and Projects Spring 5-18-2018 Improving Habitat Restoration for Native Pollinators in San Francisco Tyrha Delger [email protected] Follow this and additional works at: https://repository.usfca.edu/capstone Recommended Citation Delger, Tyrha, "Improving Habitat Restoration for Native Pollinators in San Francisco" (2018). Master's Projects and Capstones. 739. https://repository.usfca.edu/capstone/739 This Project/Capstone is brought to you for free and open access by the Theses, Dissertations, Capstones and Projects at USF Scholarship: a digital repository @ Gleeson Library | Geschke Center. It has been accepted for inclusion in Master's Projects and Capstones by an authorized administrator of USF Scholarship: a digital repository @ Gleeson Library | Geschke Center. For more information, please contact [email protected]. This Master’s Project Improving Habitat Restoration for Native Pollinators in San Francisco by Tyrha Delger is submitted in partial fulfillment of the requirements or the degree of Master of Science in Environmental Management at the University of San Francisco Submitted: Received: ……………………………. …………………………….... Your Name Date Allison Luengen, Ph.D. Date Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper Table of Contents List of Tables………………………………………………………………………………………....1 List of Figures………………………………………………………………………………………..2 Abstract……………………………………………………………………………………………….3 Introduction…………………………………………………………………………………………..4 Why Pollinators are Important……………………………………………………………….4 The Species…………………………………………………………………………………....6 Callophrys viridis: Green Hairstreak Butterfly…………………...………………..7 ​ Icaricia icarioides missionensis: The Mission Blue Butterfly…………………...10 ​ Bombus californicus: The Californica Bumblebee……………………………….11 ​ Objective of the Paper……………………………………………………………………....13 Methods………………………………………………………………………………………………..14 Conservation Inside and Outside the City………………………………………………………....16 Callophrys viridis……………………………………………………………………………..16 ​ Icaricia icarioides missionensis…………………...……………………………………….19 ​ Bombus californicus………………………………………………………………………....26 ​ Special Considerations for Urban Areas…………………………………………………………...30 Apis mellifera: The Western Honeybee…………………………………………………...30 ​ Air Pollution…………………………………………………………………………………..37 Habitat Fragmentation……………………………………………………………………....38 Other Cities’ Restoration and Conservation Strategies…………………………………………..41 Chicago’s Rooftop Gardens………………………………………………………………...46 New York City’s Networks and Sidewalk Gardens…..………………………………….49 Management Suggestions…………………………………………………………………………..55 Species Specific Suggestions………………………………………………………………55 Mixed Use Habitats………………………………………………………………………….57 Involve the Community………………………………………………………………….......58 Government, Community, Non-for-profits, and Scientists……………………………….62 San Francisco Habitat Restoration………………………………………………………...66 Conclusion…………………………………………………………………………………....71 Literature Cited………………………………………………………...……………………………..74 Appendix……………………………………………………………………………………………....82 1 Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper List of Figures Figure 1: San Francisco Green Spaces Map……………………………………………………….5 Figure 2: C. viridas on Seaside Daisy……………………………………………………………….8 ​ ​ Figure 3: Three Lupines……………………………………………………………………………...11 Figure 4: Map of Green Hairstreak Corridor……………………………………………………….17 Figure 5: Volunteers restoring habitat……………………………………………………………...18 Figure 6: Map of Twin Peaks, San Francisco……………………………………………………..21 Figure 7: Graph showing the results of species transplants……………………………………..24 Figure 8: Graph showing differences in biomass………………………………………………….28 Figure 9: Graph showing different rates of visitation……………………………………………...29 Figure 10: A. mellifera………………………………………………………………………………..31 ​ ​ Figure 11: Deformed wings and Mites for DWV…………………………………………………...34 Figure 12: 1-hr ozone max graph…………………………………………………………………...38 Figure 13: 8-hr ozone max graph…………………………………………………………………...39 Figure 14: Graph showing B. californicus seasonality…………………………………………....40 ​ ​ Figure 15: Edge Effects……………………………………………………………………………...42 Figure 16: Existing park space, San Francisco…………………………………………………...44 Figure 17: Chicago City Hall Rooftop Garden……………………………………………………..46 Figure 18: Sidewalk garden, New York City……………………………………………………….50 Figure 19: Labeled sidewalk garden, New York City……………………………………………..53 Figure 20: Community involvement, Nature in the City…………………………………………..59 Figure 21: Brochure of Green Hairstreak Corridor………………………………………………..61 Figure 22: Photo of Blue Blossom………………………………………………………………….68 Figure 23: Potential sidewalk garden map………………………………………………………...69 Figure 24: Photo of Alamo Park…………………………………………………………………….70 2 Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper List of Tables Table 1: Species Table………………………………………………….………………..…………...7 Table 2: Mission Blue Butterfly monitoring………………………………………………………...22 Table 3: Chicago species richness………………………………………………………..……….48 Table 4: Percentage of bee species, New York City……………………………………...………51 Table 5: Comparison of richness and species…………………………………………………….51 Table 6: Percentage of species per nesting material……………………………………………..52 Table 7: Benefits, problems, and successes……………………………………………………....56 3 Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper Abstract Pollinators are responsible for 67 to 98% of flowering plant reproduction while 90% of all plants are flowering. This does not change in urban environments and focusing on habitat restoration in cities is important for the conservation of species. This paper focuses on urban habitat restoration in San Francisco for three species: Callophrys viridis, Icaricia icarioides missionensis, and ​ ​ ​ ​ Bombus californicus. These three species are all native of San Francisco and are all threatened by ​ loss of habitat within the city. The problems these species face in urban environments, as well as the successes and failures of other habitat conservation programs, can help conservationists better design projects to improve native pollinator population. The organizations planning these restoration projects need to understand how the species interact with the environment. Bombus ​ californicus requires ground-nesting habitat while Icaricia icarioides missionensis requires three ​ ​ ​ lupine species for larval feeding. As seen with New York City’s sidewalk gardens and the success of I. icarioides missionensis population restoration on San Bruno Mountain, having a ​ ​ combination of scientific, community, government, and non-for-profit interest helps restoration projects become a success. C. viridis only has community and non-for-profit interest in the form ​ ​ of Nature in the City while B. californicus has some scientific interest, but little else. To ensure ​ ​ that these species, as well as others are properly conserved, the City of San Francisco must get involved with planning efforts, especially when it comes to caring for parks. It is also important that non-for-profits and community involvement be encouraged in the form of citizen science and smaller gardens and sidewalk gardens to create pollinator networks. By having this level of involvement, the city of San Francisco can become a haven for native pollinators. 4 Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper Introduction City environments are often seen as unsuitable areas for habitat restoration. The dense population of humans, restructuring the entire ecosystem, and other anthropogenic effects make it difficult to support native plants and animals within city limits. However, cities are not separate from the environment, they are a part of it. To assume that because cities have a condensed human population they cannot be useful for conservation is incorrect and damaging to species that have a small habitat range (Wouter and Dyke, 2007). Cities can provide viable and useful habitat for pollinators, if restoration managers, land planners, and environmental organization know how to design, how to research, and how to improve these projects. Why pollinators are important Pollinators are one of the most important parts of an ecosystem. Flowering plants (angiosperms) make up 90% of all plants, and 67 to 98% of all angiosperms require pollinators (Ollerton et al., 2011). This is still true in city environments. Urban green spaces can help beautify the city, provide recreation areas, ease the burden on storm sewers, and help reduce the urban heat island effect (City Planning Commission, 2008). San Francisco boasts having 220 parks (see Figure 1), totalling 5,693 acres (23.04 square kilometers) of park space (Harnik et al., 2016). Those parks are filled with flowering plants like the California Poppy (Eschscholzia ​ ​ ​ californica) and Blue Blossom (Ceanothus thyrsiflorus) that require pollinators to survive. ​ ​ ​ Ecosystems with pollinators are healthier and have a greater amount of species richness; increasing the diversity of flowers, birds, and other insects. (Wouter and Dyke, 2007). 5 Name: Tyrha Delger USF MSEM Master’s Project Spring 2018 Final Paper Figure 1: Image of San Francisco’s Green Space (Harnik et al., 2016). While it may seem as though nature reserves and national parks are adequate enough to protect native pollinator populations, they are not. Some pollinators only have habitat