The Marin Islands are located offshore from the city of San Rafael, in the northern San Francisco Bay Area. The islands comprise the Marin Islands National Wildlife Refuge, which was established in 1992. The surrounding submerged tidelands are also included in the refuge. The islands are the property of the U.S. Fish and Wildlife Service and require special permission to visit.
The islands were donated to the federal government by the Crowley family of San Francisco. They had been bought by Thomas Crowley at auction in 1926 for $25,000 in the hope that they would become the western terminus of the Richmond–San Rafael Bridge. Instead, they became a family vacation spot for more than sixty years.
East Marin Island, a former vacation retreat, now supports a variety of introduced and native plants and provides critical nesting material and rest sites for the nearby colony.
The submerged tidelands support a variety of resident and migratorywater birds such as surf scoter, black oystercatcher, diving ducks, and osprey. Refuge objectives are to protect migratory species, including the heron and egret nesting colony, protect and restore suitable habitat for the colony, and protect the tidal mud flats and unique island ecosystem.
^Goerke, Betty. 2007. Chief Marin, Leader, Rebel, and Legend: A History of Marin County's Namesake and his People. Berkeley: Heyday Books. ISBN978-1-59714-053-9