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Volunteer Invasives Mapping Project Report

Display Report


First Year of Project
Station: San Pablo Bay NWR/Marin Islands NWR
Region: 8
Contact Person: Giselle Block
Contact Phone Number: 707-769-4200
Date Report Submitted:

List Type and/or Affiliation(s) of Volunteers: Refuge
Total Number of Volunteers Trained to Map: 25
Total Number of Volunteer Hours Spent Mapping: 2880

List of Invasives Species Mapped:Common NameScientific Name
  pepperweed Lepidium latifolium
smooth cordgrass Spartina alterniflora
dense-flowered cordgrass Spartina densiflora
stinkweed Dittrichia graveolens
iceplant Carpobrotus edulis
pampass grass Cortaderia selloana
erect veldtgrass Ehrharta erecta
French broom Genista monspessulana
Bermuda buttercup Oxalis pes-caprae
Which, if any, of these Species are Early Detection Species: S. alternifloa, S. densiflora, E. erecta
Total Number of Acres Mapped (since project initiation): 3,611 (SPBNWR), 10 (MINWR)-does not include multiple years of re-assessments following control-not sure what to report here-acres searched, infested acres, gross acres?
Have You Shared Mapping Data with USGS in Ft. Collins? Yes

Describe Projects Initiated with Follow-Up Funds ($10,000): Several projects have been initiated since 2004 as a result of the Refuges’ capacity to develop and implement an invasive plant program. Mapping invasives is now an integral part of the San Pablo Bay NWR program and allows the Refuge to evaluate and adapt control or eradication efforts, to engage volunteers, and to raise funds. Projects initiated since 2004 include a large scale effort to control pepperweed in tidal marsh of the Refuge. This pepperweed program is in its 5th year, including 3 years of treatment on some areas of the Refuge. The program is expanding into new areas each year. A small scale study of control efforts, effects on non-target native species, and comparison of treatment methods has been completed. Data analysis is underway and a manuscript will be prepared. This project represents the first large-scale treatment of pepperweed in the SF Estuary. Oral presentations have been given at the California Invasive Plant Council (2008) and the SF Estuary Lepidium Symposium (2008). Other projects that have begun on San Pablo Bay NWR include early detection and rapid response actions on invasive Spartina species (S. densiflora, S. alterniflora hybrids). This effort is in coordination with the Invasive Spartina Project (CA Coastal Conservancy). In addition to pepperweed, invasive Spartina species pose one the most significant threats to the tidal marsh ecosystem of the SF Estuary. These species were detected in small colonies on the Refuge in 2007 and have been mapped and treated in 2008 and 2009. At the Marin Islands NWR we have begun to incorporate mapping to evaluate control of the most invasive species identified in the 2005 Vegetation Management Plan. These include French broom, oxalis, and erect veldtgrass. In conjunction with invasive plant control or eradication on San Pablo and Marin Islands NWR’s has been the restoration of native plant communities. A native plant nursery was established in 2006 at the San Pablo Bay NWR headquarters. Local seed sources are collected, propagated, and planted out each year. Volunteers participate at all levels in this effort, especially through partnerships with non-profit agencies such as the Bay Institute and National Audubon.
Total Number of Acres Treated with Follow-up Funding: 302.5 (SPB+MINWR combined)
Total Number of Acres Restored with Follow-up Funding: 1,500 (San Pablo), 2 (Marin Islands)
Total Number of Volunteers Engaged in Treatment and/or Restoration: 615 (SPB+MINWR combined)


How has this Project Benefited Invasive Species Management Efforts at Your Station? The Volunteer Invasives Mapping Project has allowed San Pablo Bay NWR to develop and implement a program focused on control of invasive plant species and restoration of native plant assemblages. The program has also expanded to Marin Islands NWR. Much of the annual follow-up funds (e.g., 10K) have been used to build the infrastructure for our mapping program (e.g., GPS units, kayaks, field supplies) and to hire interns for mapping, coordinating volunteers, and related restoration. The initial training, base funds, and subsequent mapping efforts have provided significant leverage for obtaining additional grants to fund large-scale treatment, native plant propagation and planting (restoration), and education. We have built several new partnerships as a result of this program: The Bay Institute, Save the San Francisco Bay Assoc., Sonoma Land Trust, CA Dept. of Fish and Game, Marin-Sonoma Weed Mgt. Area, National Park Service, Audubon California, and other refuges.
What are some of the Lessons Learned and/or Troubleshooting Points that could be Shared with Others Engaged in Similar Activity?
Choose a mapping method that matches your current level of technical expertise and build from there. Start somewhere and don't feel intimidated by the technology and the software. Be willing to adapt your methods in the future. Use your baseline maps to identify treatment polygons...no need to field map treatments. Seek partnerships, join your local weed mgt. area if you have one, join state or national organizations that combat invasives, attend invasive org. meetings/conferences, treat your volunteers really well, leverage your volunteers as in-kind $ to raise additional funds for control/restoration.


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