Richardson Bay

Richardson Bay
Richardson Bay viewed from Mount Tamalpais
Richardson Bay Location of Richardson Bay across from San Francisco
Location	San Francisco Bay
Coordinates	37°52′30″N 122°29′00″W / 37.87500°N 122.48333°W / 37.87500; -122.48333
Type	Bay
Etymology	William A. Richardson
Primary inflows	Arroyo Corte Madera del Presidio, Coyote Creek
Average depth	20 ft (6.1 m)

Richardson Bay (originally Richardson's Bay) is a shallow, ecologically rich arm of San Francisco Bay, managed under a Joint Powers Agency of four northern California cities.^[1] The 911-acre (369 ha) Richardson Bay Sanctuary was acquired in the early 1960s by the National Audubon Society.^[2] The bay was named for William A. Richardson, early 19th century sea captain and builder in San Francisco. It contains both Strawberry Spit and Aramburu Island.

In spite of its urbanized periphery, Richardson Bay supports extensive eelgrass areas and sizable undisturbed intertidal habitats. It is a feeding and resting area for a panoply of estuarine and pelagic birds, while its associated marshes and littoral zones support a variety of animal and plant life. Richardson Bay has been designated as an Important Bird Area (IBA), based upon its large number of annual bird visitors and residents, its sightings of California clapper rail and its strategic location on the Pacific Flyway. The bay's waters are subject to a "no discharge" rule to protect the elaborate and fragile ecosystems present, including a complex fishery, diverse mollusk populations and even marine mammals such as the harbor seal.

Owing to its lack of depth and complicated channel structure, Richardson Bay is limited in boating uses to kayaking and small sailing craft. There are extensive hiking and bicycling paths at the bay perimeter, especially in the shore areas of Mill Valley and the town of Tiburon.^[3]