Tomales Bay

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Tomales Bay

  • Country: 
    United States of America
  • Site number: 
  • Area: 
    2,850 ha
  • Designation date: 
  • Coordinates: 
    38°09'N 123°23'W
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Tomales Bay. 30/09/02. California. 2,850 ha. 38°09'N, 123°23'W. Part of Marine Sanctuary. Tomales Bay is a marine-coastal wetland consisting of geomorphologicaly dynamic estuaries, eelgrass beds (Zostera marina), sand dune systems, and restored emergent tidal marshes which floods the northern 20 km of the San Andreas Fault-generated Olema Valley on the central California coast. The site fulfills all eight Ramsar Criteria. Approximately 90% of the bay's 28.5 km2 area is subtidal with a much greater area of open water at low tide than most other Pacific coast estuaries, thus becoming a suitable waterbird habitat through the tidal cycle. Because the 58,000 ha. watershed is non-industrial and has a low human population density, the bay is relatively pristine. The site supports several endangered or threatened plant and animal species, and is an important waterbird migratory stopover site and over-wintering ground along the Pacific flyway - it regularly hosts over 20,000 individuals in the winter months, most notably of surf scoter (Melanitta pespicillata), bufflehead (Bucephala albeola), and greater scaup (Aythya mariloides). In the past, the site has been affected by industrial and agricultural activities, which have since been terminated or mitigated. Local authorities and private and non-governmental organizations have conducted a number of watershed protection measures and conservation and restoration projects over the past 40 years in the area. Ramsar site no. 1215. Most recent RIS information: 2002.

Administrative region: 

  • National legal designation: 
    • State Park - Tomales Bay
  • Last publication date: 


Ramsar Information Sheet (RIS)