Castro Rocks

Summary

The Castro Rocks are several rocks in Richmond, California protruding from the waters in San Francisco Bay between Castro Point and Red Rock Island. The rocks lie almost directly under the Richmond-San Rafael Bridge (I-580).[1]

Castro Rocks with harbor seals

Name edit

 
The Castro Rocks are named after Don Víctor Castro, a Californio ranchero and politician.

The rocks are named after Don Víctor Castro, a local rancho-era land owner.[citation needed] They are shown as "Castro Rocks" on an 1850 survey map of the San Francisco Bay area made by Cadwalader Ringgold.[2]

Harbor seals edit

Castro Rocks are the home of many harbor seals,[3] which lie on them to rest and sunbathe. The rocks are the largest harbor seal rookery in the northern San Francisco Bay and the second largest in the Bay Area itself.[4] There are also sometimes sea lions on the rocks.[5] The rock's Harbor Seals also frequent Mowry Slough, Brooks Island, Yerba Buena Island, and Mare Island.[6]

The seals at this location have high levels of toxic pollutants including the DDT, PCBs, PBDEs, PFOS, PFOA, and mercury.[7]

References edit

  1. ^ Topographic map, TopoQuest, retrieved July 6, 2008
  2. ^ Ringgold, Cadwalader; Stuart, Fred D.; Everett, Chas.; Harrison (1850). "General Chart embracing Surveys of the Farallones Entrance to the Bay of San Francisco, Bays of San Francisco and San Pablo, Straits of Carquines and Suisun Bay, and the Sacramento and San Joaquin Rivers, to the Cities of Sacramento and San Joaquin, California". David Rumsey Map Collection. San Francisco Common Council. Retrieved 25 February 2021.
  3. ^ Tagging program Archived 2007-09-09 at the Wayback Machine, SFSU, retrieved August 1, 2007
  4. ^ SFSU Archived 2007-09-06 at the Wayback Machine, Castro Rocks page, retrieved August 1, 2007
  5. ^ NOAA Seeks Comments On A Proposed Reauthorization For California Department Of Transportation To Harass Seals During Bridge Reconstruction Archived 2008-02-12 at the Wayback Machine, NOAA Press Release, February 12, 1999, retrieved August 4, 2007
  6. ^ vhfmapweb.jpg Archived September 11, 2007, at the Wayback Machine, Radio tagging map, San Francisco State University, February 2004, retrieved August 4, 2007
  7. ^ Harbor seals may help determine effect on humans of eating toxic fish, by Jane Kay, San Francisco Chronicle, 19-10-2009, access date 19-02-2009

External links edit

  • Castro Rocks page
  • SFSU Tagging - Photos

37°55′58″N 122°25′01″W / 37.932817°N 122.416963°W / 37.932817; -122.416963