Abstract

The Aramburu Island Ecological Enhancement Project (Project) is located on and adjacent to Aramburu Island in Richardson Bay, Marin County, California (Figure 1). The 17-acre island was originally part of Strawberry Spit, which was constructed in the late 1950s and early 1960s by the deposition of navigational dredging spoils and upland fill in the open waters of Richardson Bay. The island became a popular haul out site for harbor seals (Phoca vitulina) during the 1960s and 1970s. The northern portion of Strawberry Spit was made into Aramburu Island in 1987 by excavating a navigation channel in the middle of the Spit. The San Francisco Bay Conservation and Development Commission (BCDC) required creation of this shorebird and harbor seal refuge island as a permit condition for housing development on the spit. Following island creation, the developer deeded the island and its surrounding waters (a parcel 35.81 acres in total) to the Marin County Department of Parks and Open Space.

The Project purposes are to (1) increase the stability of the eroding eastern shoreline, (2) enhance and create aquatic, wetland and terrestrial habitats to support a range of target species and natural communities, and (3) provide a platform for ecosystem adaptation to sea level rise, allowing for gradual dynamic transitions. In addition, the Project seeks to meet the adjacent residents’ goals of (1) not enhancing or creating habitats that would attract the state and federally listed endangered California Clapper Rail (Rallus longirostris obsoletus) that could interfere with their maintenance dredging permits, (2) not affecting sediment dynamics in the navigation channels that would affect maintenance dredging, (3) preserving existing view sheds, and (4) not encouraging increased public access to the island.