| Richardson Bay | |
|---|---|
 Richardson Bay viewed fromMount Tamalpais | |
  Richardson Bay Location of Richardson Bay across from San Francisco | |
| Location | San Francisco Bay |
| Coordinates | 37°52′30″N122°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 (originallyRichardson's Bay) is a shallow,ecologically rich arm ofSan Francisco Bay, managed under by theRichardson Bay Regional Agency, created under a joint powers agreement by theCounty of Marin, Town ofTiburon, and Cities ofBelvedere andMill Valley.[1] The 911-acre (369 ha) Richardson Bay Sanctuary was acquired in the early 1960s by theNational Audubon Society.[2] The bay was named forWilliam A. Richardson, early 19th centurysea captain andbuilder inSan Francisco. It contains bothStrawberry Spit andAramburu Island.
In spite of its urbanized periphery, Richardson Bay supports extensiveeelgrass areas and sizable undisturbedintertidal habitats. It is a feeding and resting area for a panoply ofestuarine andpelagic birds, while its associatedmarshes andlittoral zones support a variety of animal and plant life. Richardson Bay has been designated as anImportant Bird Area (IBA), based upon its large number of annual bird visitors and residents, its sightings ofCalifornia clapper rail and its strategic location on thePacific Flyway. The bay's waters are subject to a "no discharge" rule to protect the elaborate and fragile ecosystems present, including a complexfishery, diversemollusk populations and evenmarine mammals such as theharbor seal.
Owing to its lack of depth and complicated channel structure, Richardson Bay is limited in boating uses tokayaking and smallsailing craft. There are extensivehiking andbicycling paths at the bay perimeter, especially in the shore areas ofMill Valley and thetown of Tiburon.[3]
On August 22, 1822, an Englishwhaler, the Orion, put into Yerba Buena Cove in San Francisco for supplies; the captain wasWilliam Anthony Richardson, described as tall, fair haired, blue-eyed and young, was sighted by Maria Antonia, daughter of the Commandante of thePresidio of San Francisco,Ygnacio Martinez. Martinez, for whom the town ofMartinez is named, decided to invite the Captain to reside with their family. Maria married the captain after he joined theCatholic Church, being baptized "Guillermo Antonio Richardson." This wedding, held atMission Dolores on May 12, 1826 was the first great Spanish-Anglo Saxon wedding in North America.[4][5]
Richardson taughtcarpentry, boat building andnavigation atMission Dolores, served as Captain of thePort of San Francisco, and built the first significant residence in San Francisco, although it was meant to be a trading post. He had charge of severalschooners belonging to the Mission Dolores andMission Santa Clara. Richardson received a 19,500-acre (79 km2)Mexicanland grant in 1838,Rancho Saucelito, which is all of the land north of theGolden Gate extending from bay to ocean and ranging north toMount Tamalpais The grant contained all the land southeast ofMount Tamalpais, and included Redwood Canyon and the lands now withinMuir Woods National Monument. Richardson Bay was thus named in the honor of this energetic earlysettler and builder.
TheTiburon Peninsula on the northeast side of the bay was part ofRancho Corte Madera del Presidio granted toJohn Thomas Reed in 1834.
According to local sources[6][7] and period maps,[8] the Bay's original given name was possessive:Richardson's Bay. However, theUnited States Board on Geographic Names discourages the use of apostrophes in United States place names,[9] which is why the name appears asRichardson Bay in government databases[10] and maps.[11]
Richardson Bay is developed on surficialsediments ofclays,silts and minorsands andgravels deposited in a primarily marine and estuarine environment during periods of previous high stands of water relative to the present shoreline. Thebay muds are widespread in San Francisco Bay and, at Richardson Bay, are approximately 80 to 95 feet (24 to 30 meters) deep[1].[12] The Bay Muds are of Holocene Age (less than 10,000 years of age). They overlie firm alluvial soils which contain two sand layers at 92 and 110 feet (29 and 35 meters), respectively. This section, in turn, overliesshale of theFranciscan Complex, a heterogeneous mixture ofsedimentary,igneous andmetamorphic rock gathered together in the course of the tectonic evolution of the region from the Late Jurassic to the MiddleMiocene. These assemblages of Franciscan rocks are referred to astectonostratigraphic terrains and two of them, the Central Belt and the Coastal Belt, are in fault contact near Richardson Bay.
Richardson Bay is an important ecological area being managed by Audubon California as the Richardson Bay Audubon Center & Sanctuary.[2] There are significantestuarine resources,marshbirdlife,mammalian species and marsh plants.[13]
Birds are abundant in Richardson Bay, with over one million migratory visitors each winter, many of whom utilizing the upper mudflats and Bothin Marsh associated with the area west of theU.S. Route 101. In addition to being designated a high scoreIBA, Richardson's Bay has been dedicated as a Hemispheric Reserve of the Western Shorebird Network. Migrating birds that winter regularly at Richardson's Bay includeleast sandpiper,western sandpiper,spotted sandpiper,American avocet,dunlin,marbled godwit,greater yellowlegs,willet,long-billed curlew anddowitchers[2]. A special resident[3] of Bothin Marsh, Blackies' Creek mouth and DeSilva Island is theCalifornia clapper rail, a non-migratoryendangered species.[2] Beginning in 2014,endangeredblack oystercatchers have been observed nesting on Aramburu Island.[14]
Common year around residents of the Richardson Bay Sanctuary includegreat blue heron,snowy egret, andgreat egret;mallard;red-tailed hawk andturkey vulture;killdeer andwestern gull;mourning dove androck dove;Anna's hummingbird. Common residentsPasseriformes includescrub jay,American crow,chestnut-backed chickadee,bushtit,Bewick's wren,house sparrow,red-winged blackbird,house finch,California towhee andsong sparrow.[15]
Fishery characteristics of Richardson Bay include aPacific herringfishery andoyster beds. The herringfishing fleet serving all of San Francisco Bay is based in Richardson Bay at the Sausalito harbor. This herring fishing is overseen by theCalifornia Department of Fish and Game; the herring population is in a downward trend, although not from excessivefishing pressure with the net techniques in use, but rather from ocean environmental factors. Herring spend most of their lives in the open ocean and come to Richardson Bay and other estuaries for winter spawning in the shallow protected waters. In Richardson Bay their eggs attach to assorted surfaces such as eelgrass,[16] piers orrip rap. After the eggs hatch, the herringlarvae consumeplankton; before hatching the eggs are subject to predation bygulls at low tide andsturgeon and other assorted estuarine fauna at higher tides.
Regarding the oyster beds, an experimental program is underway as of 2006, in which foreign oyster shells (biologically inert) are bagged and em-placed in underwater locations to serve as larval substrates, in order to assist the native oysters in propagating. Locally oysters are preyed upon by thebat ray and certaincrabs.
The extensivemudflats of Richardson Bay provide a richhabitat formarine invertebrates. Many of the species are found elsewhere in San Francisco Bay. Characteristic organisms include burrowingclams,polychaete worms, decapodcrustaceans,amphipods,phoronids andanemones. A field survey conducted on a broad mudflat along the Strawberry/Belvedere shoreline found species associated with rocks including:bivalves, (Macoma balthica,Mya arenaria andMytilus edulis); thesea snailLittorina planaxis; thecrabHemigrapsis oregonensis; theisopodSphaeroma quoyanum; thebarnaclesBalanus glandula andBalanus amphitrite; thenemerteanLineus ruber; and theanemonesDiadumene leucolena andHaliplanella luciae.[4]
Mammals visiting Richardson Bay include theharbor seal, which hauls out onDeSilva Island and on the Tiburon shore near the Richardson Bay Audubon Sanctuary headquarters. Theendangeredsalt marsh harvest mouse is also thought to be present.
Flora includeintertidal and upland species. Probably the most notable feature is the extensiveeelgrass population at the tideland perimeter of Richardson Bay. This eelgrass occurrence in Richardson Bay is considered one of the most sizeable stands in Northern California, and it is being restored, leading to further extent of this habitat. There is an extensivepickleweed habitat at the western end of the bay, where many acres of mudflat areas are exposed toshorebirds at low tide at the efflux ofPickleweed Inlet. Upland plants found at the perimeter of Richardson's Bay includetoyon,coast live oak,California bay, and native Californiabunch grasses.
On November 7, 2007, there was a largeoil spill in theSan Francisco Bay[5].[17] This Cosco Busan oil spill was found to be lethal to herring fry in oiled versus non-oiled sites in Richardson Bay.[18] This spill has greatly affected theorganisms in thebay.
Through the latter 19th century and early 20th century, the land fronting on Richardson Bay was extensively subdivided into public and private ownership encompassing thousands of parcels. The cities of Tiburon, Mill Valley, Belvedere and Sausalito have enacted strong shoreline development policies to protect the perimeter of Richardson Bay, even though considerable development has occurred. The Audubon Society manages the whole Richardson Bay Sanctuary subject to governance by the Joint Powers Agency of the four peripheral cities.
One parcel deeded from Reed to Rosie Verall, who worked for the Reed family, is now the core of the Audubon Richardson Bay Sanctuary. Verall donated this land of approximately 13 acres (5.3 ha) to be held in permanent trust as awildlife sanctuary. The Audubon Society purchased this upland parcel along with the entirety of the subtidal and intertidal lands of Richardson Bay in 1960. The Lyford House built in 1876 occupies the Verall parcel, even though the house was built at a different location in the vicinity known as Strawberry Point. The house is furnished in period style and is used by theNational Audubon Society for special functions and events.
As of 2019, the bay contains about one hundred people who live on boats one-quarter mile from the shore.[19]
Richardson bay joinsSan Francisco Bay where the water depth becomes 20 feet (6 m), demarcated by a highly irregular boundary connecting the southern end of the Sausalito Marina] with the southern tip of Belvedere, sometimes called Peninsula Point. At this line of demarcation the depth increases rapidly on the San Francisco Bay side, becoming 100 feet (30 m) in depth almost immediately. This portion of San Francisco Bay, also known asRaccoon Strait, possesses highly turbulent waters. Boating in Richardson Bay is limited to small sailing craft andkayaks due to limiteddraft available, and nearly 900 acres of the bay is closed for six months during the winter each year to provide protection for the ecological system, particularly migratory waterbirds.
Richardson Bay receives inflow from numerous seasonal small unnamed streams and three major streams:Arroyo Corte Madera del Presidio which receives thesurface runoff from the steep southeast slopes ofMount Tamalpais;Pickleweed Inlet; andCoyote Creek (Marin County), which receives the runoff from the slopes to the west of Richardson Bay. These streams empty into Richardson Bay from the northwest. Arroyo Corte Madera del Presidio and Coyote Creek are intermittent in flow.[20]
The National Audubon Society operates anature center in Tiburon that offers adult and children's nature programs, including summer camp, school science programs, birthday and family events, lectures, guided walks, environmental education workshops, Bay Shore Studies docent programs and volunteer projects. Recent efforts included renovation of the human-made islands Aramburu,[21] Pickleweed, and Unnamed[14] to enhance their value as bird refuges.
Map: Islands of theSan Francisco Bay Area | |
|---|---|
 |
