Biological Invasions

, Volume 18, Issue 8, pp 2247–2266 | Cite as

A review of 15 years of Spartina management in the San Francisco Estuary

  • Drew W. KerrEmail author
  • Ingrid B. Hogle
  • Brian S. Ort
  • Whitney J. Thornton


Regional, ecosystem-level conservation projects with significant vegetation management components require planning, coordination, and responsive management strategies to minimize negative impacts and maximize ecological benefits over time. The California State Coastal Conservancy’s Invasive Spartina Project (ISP) offers an example of a complex, ecosystem-scale weed eradication effort guided by regional conservation goals. We review the management framework developed by the ISP, describe decision thresholds used for site-specific management transitions over the project’s 15 years, and present strategies being used to address major challenges to project completion. These strategies include developing genetics and weed mapping approaches to aid with identification of hybrids between the introduced Spartina alterniflora and the native Spartina foliosa. The ISP also developed a tidal marsh restoration project to enhance habitat for an endangered bird, the California Ridgway’s rail (Rallus obsoletus obsoletus), that uses tall, dense forms of hybrid Spartina as high tide refugia and nesting substrate. By 2014, the ISP had installed over 300,000 native plants and recorded a greater than 96 % estuary-wide reduction in hybrid Spartina (from 323 ha to 12 net ha) despite treatment restrictions imposed at 11 sites since 2011 to protect the rail. Approximately 80 % of the remaining hybrid Spartina occurs in areas currently restricted from treatment, delaying project completion. The successes and setbacks of the ISP illustrate the complexities of achieving ecosystem-level conservation goals dependent on large-scale vegetation management.


Hybridization Spartina San Francisco Estuary Management Invasive plants Restoration Mapping 



We gratefully acknowledge the outstanding commitment of the California State Coastal Conservancy to manage and fund this unprecedented, ongoing effort to eradicate invasive Spartina before it spreads outside the San Francisco Estuary. The Conservancy’s San Francisco Estuary Invasive Spartina Project has received funding from the following sources: California State Coastal Conservancy, State Wildlife Conservation Board, CALFED Bay Delta Program, USFWS, American Reinvestment and Recovery Act through National Oceanic and Atmospheric Administration, U.S. Environmental Protection Agency, Gordon and Betty Moore Foundation, David and Lucile Packard Foundation, S. D. Bechtel Jr. Foundation, North American Wetlands Conservation Act, and National Coastal Wetlands Conservation Grant Program. We are grateful to our co-workers, partners, grantees and contractors, past and present, for their invaluable contributions to the ISP’s regional coordination, mapping, treatment and revegetation efforts. Jen McBroom made important contributions to this paper regarding Ridgway’s rail. Tobias Rohmer, Peggy Olofson, and Thom Sayles provided excellent editorial suggestions. Two anonymous reviewers provided suggestions to substantially improve the structure of the paper. We thank the organizers of the 4th International Conference on Invasive Spartina in Rennes, France (July 2014) and the editor for inviting submittal of manuscripts associated with the conference.


The San Francisco Estuary Invasive Spartina Project is funded by the California State Coastal Conservancy. Authors WJT and BSO are employees of Olofson Environmental, Inc., and authors DWK and IBH are independent contractors to Olofson Environmental, Inc., a private company that receives funding from the Conservancy. All four authors work on the ISP.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Drew W. Kerr
    • 1
    Email author
  • Ingrid B. Hogle
    • 1
  • Brian S. Ort
    • 1
    • 2
  • Whitney J. Thornton
    • 1
    • 2
  1. 1.San Francisco Estuary Invasive Spartina ProjectOaklandUSA
  2. 2.Olofson Environmental, Inc.OaklandUSA

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