Aramburu Island

Learn about this island enhancement project right here in Richardson Bay!

The Aramburu Island Enhancement Project

The project site is located in Richardson Bay, a short boat ride from our center in Tiburon.
The 17-acre island was created in the early 1960s by dredge spoils and fill from nearby development. Though protected as a preserve, Aramburu received little attention over the years. Invasive, non-native plants dominated the island and waves pounded the shoreline, causing up to 6 feet of erosion per year.
Following the Cosco-Busan oil spill in 2007, Audubon staff observed that the majority of birds in Richardson Bay were using Aramburu Island as a refuge from toxic waters. Seeing this need for habitat sparked the plan for an enhancement project. Audubon and its partners spent two years fundraising, planning, and permitting the project.
The Enhancement Plan was designed to improve aquatic, wetland, and upland habitats for a range of local species, stabilize the rapidly eroding eastern shoreline, and help the island and surrounding communities adapt to sea level rise. Construction was completed by November of 2012.

Tidal Marshes: Enhancing a disappearing habitat

Over the last two centuries, more than 90% of important tidal mud flat and marsh habitats in the San Francisco Bay have been destroyed. The Aramburu Island Enhancement Project created unique and important wetland, beach, and terrestrial habitats for birds and wildlife. 

Constructing a Precedential Shoreline 

The Aramburu shoreline was planned with a focus on creating habitat for terns and other water birds. Since 2013, Audubon staff and volunteers have counted groups of nearly 400 Elegant Terns, over 1000 overwintering Double Crested Cormorants, and hundreds of sandpipers and plovers on Aramburu’s beaches;  many other shorebirds were observed foraging, resting and roosting on the island.

In 2014, Aramburu Island became one of only four known successful nesting sites for Black Oystercatchers within San Francisco Bay! Black-necked Stilts and Killdeer have also nested successfully, yet another sign that the restored shoreline is providing high-quality habitat.  

2015: A new year for Aramburu Island: Year 3 of Island Revegetation

In our first winter of planting, January 2013, Richardson Bay Audubon Center & Sanctuary’s Restoration team (with the help of a contracted planting crew and numerous volunteers) planted 20,000 new native salt marsh and grassland plants on Aramburu. The following year, winter 2013-2014, our team planted an additional 16,000 plants on Aramburu. Both years we were hit by strenuous drought that reduced plant survivorship. Canada Geese also remain a challenge, as they like to eat the young native plants. Being challenged by these environmental factors led us to adapt new management practices this year as we entered our third year of revegetation. We doubled our planting numbers, installed irrigation systems, and started experimenting with goose-repelling strategies.

This year, our restoration team invested some much needed time and energy into ensuring higher survivorship of our plants. We purchased and installed goose prevention cages by hand on most of our irresistibly juicy green grassland plants. We made creative use of our irrigation system, increasing efficiency by disconnecting overhead sprayers and instead attaching garden hoses with pressure nozzles. As a result, we have less evaporation occurring in the air (especially during hot, dry weather), and more going directly to plant roots. This has also aided in our water conservation efforts on the island as we have a very limited amount of fresh water available.

By investing time, energy and funds into plant survivorship we currently have a high success rate in this years’ focal habitats. Healthy, green are leaves popping out of Aramburu’s northern vernal pond, western oak grove and salt grass meadow, and southern grass sedge meadow habitats. This year’s planting and seeding efforts gave an additional 5,000+ new native plants and approximately 2 acres of seed coverage to Aramburu Island’ diverse microhabitats. As we continue on through this dry spring, we transition our efforts to sustaining our new plants through watering (only through April so that they become tolerant of California’s natural drought summer) and removing non-native plants.

Much of this years’ success is thanks to our many new and returning volunteers that have been a part of the project. Since July 2014 Aramburu has received help from 168 adults and 95 youth who together put in over 1,060 hours restoring the island!

What's Next? Today through 2021

While much progress has been made on Aramburu, there is still work to be done! Audubon will continue to plant native species, remove invasives, monitor birds and vegetation, maintain the shoreline, and continue work to improve habitats and ecosystems on the island through 2021.

Join Our Efforts! 

Finally, we encourage volunteers and guests interested in seeing the Aramburu restoration project to attend one of our regular restoration workdays.  They fun, educational, and open to the public. We plant plants (during the winter rainy season), remove invasive species, operate our irrigation systems, and use citizen scientists to help with monitoring work. We also regularly accommodate school and volunteer groups during the week. To schedule yourself or a group for a volunteer day, please email Emily Ohman, our Community Science Coordinator, at  Come check out our progress and help make Aramburu a success!

**Click this link for information on how to help!

Timeline (Updated Spring 2020)

  • Winter 2012-13: Saline irrigation and revegetation Phase 1
  • Spring-Summer 2013: Saline irrigation, invasive species management, and monitoring
  • Fall-Winter 2013-14: Island revegetation Phase 2
  • Spring-Summer 2014: Saline irrigation, invasive species management and monitoring
  • Fall-Winter 2014-15: Revegetation Phase 3
  • Spring-Summer 2015-17: Invasive species management, scientific monitoring, shorebird surveys, and data analysis
  • 2017- 2021: Scientific monitoring, public restoration workdays at Aramburu in conjunction with Marin County Parks

The Aramburu Island Enhancement Project is funded with the generous support of the following agencies and foundations.
Costco Busan Oil Spill Settlement Trustee Council
California Regional Water Quality Control Board - Cleanup and Abatement Act
Sewer Agency of Southern Marin
National Fish and Wildlife Foundation
Marin Community Foundation
Toyota Together Green grant
National Association of Counties
S.D. Bechtel Jr. Foundation
Mary Crocker Foundation

How you can help, right now