Invasive Spartina Removal and Tidal Marsh Restoration Project
Counties of Marin, Sonoma, Napa, Solano, Alameda, Contra Costa, San Mateo, Santa Clara, and San Francisco
Vital Fish, Bird and Wildlife Habitat Program.
State Coastal Conservancy (SCC) and the United States Fish and Wildlife Service (USFWS), among many others
This grant supports the continued eradication of invasive cordgrass (invasive Spartina) and enhancement of critically important tidal marsh and mudflat habitat throughout the entire nine county San Francisco Estuary. The project includes invasive Spartina monitoring and treatment, native marsh plant revegetation, California Ridgway’s rail (rail) monitoring, and community outreach and job training in partnership with the long-term Invasive Spartina Project (ISP) led by the State Coastal Conservancy (SCC) and the United States Fish and Wildlife Service (USFWS) as the state and federal leads.
Pacific cordgrass (native Spartina) is an important native species in the Estuary’s tidal marshes and mudflats as the primary plant that naturally occurs at the low intertidal zone between bay waters and tidal marsh edge. Pacific cordgrass contributes to the base of the food chain in the bay and provides critical habitat where a variety of species hide from predators, forage, and nest. Atlantic cordgrass (invasive Spartina), native to the East Coast, was introduced by the Army Corps of Engineers in the early 1970’s and subsequently hybridized with the native Spartina.
Invasive Spartina invades both tidal mudflats and marshes and scientists have documented changes in the physical structure and plant communities in these habitats, and the resulting degradation of biodiversity and habitat values for native species. The ISP is a successful regionwide collaborative effort to eradicate invasive Spartina that was started in 2000 by the SCC and USFWS. The ISP engages a network of more than 150 partners, including Cal-IPC, local, state, and federal resource agencies, non-profit organizations, local small business contractors, universities, environmental consultants, and landowners to implement the project.
This coordinated regional project is critical to the protection of native tidal marsh restoration throughout the Estuary, due to concerns of rapid and aggressive spread of the invasive species and alteration of native tidal marsh and mudflat habitats. The ISP has also been successful in securing local, state, and federal funding for continuous treatment and, as of 2019, the project has reduced the net acreage of invasive Spartina by 95%, from the high of 805 net acres in 2005 down to 38 net acres in 2019).
The ISP also includes a revegetation program to propagate and outplant native marsh plants such as Pacific cordgrass (Spartina foliosa) and marsh gumplant (Grindelia stricta). Both of these native marsh species will provide needed habitat for wildlife in the near-term and will serve as seed sources for further spread throughout nearby marshes. Both species provide nesting substrate for rails, and gumplant in particular is at a higher tidal elevation and provides the vertical structure necessary for high tide refuge.