Red Rock Island
Map SatelliteRed Rock Island, which lies several hundred meters to the south of the Richmond-San Rafael Bridge, is a minor hauling ground for the harbor seal, Phoca vitulina, and a resting site for various birds. Historically, it was a nesting site for the endangered peregrine falcon, Falco peregrinus. The aerie has not been observed since the construction of the bridge.
The island, composed of Franciscan metavolcanics, primarily chert, is the top of a submerged peak.
Integrity: Prior to 1866 the manganese deposits on the island were mined.
Use: Private
November 1979
Inventory of California Natural Areas
Revision © 2009 Steven Louis Hartman