San Mateo Rocks

Uninhabited California coastal islands

San Mateo Rocks visible in top left of this map of the western part of San Diego County, California (United States Geological Survey, 1919)

San Mateo Rocks are uninhabited islands that lie approximately 0.5 mi (0.80 km) off the coast of California,[1] to the south of San Clemente, and just north of San Mateo Point, a minor headland that marks the border between Orange County and San Diego County.[2] The rocks rise about 3 ft (or about 1 m) above high tide.[3] In 2017 the San Mateo Rocks, a pinniped haul-out and scuba destination, became part of the California Coastal National Monument.[4][5]

The Rocks first appear in the documentary record of the area in 1889, when they were described in the Coast Pilot.[3] The sloop Victoria wrecked on the rocks in a storm in 1907.[6] In 1931 the United States Coast Guard reserved the location (along with several other Orange County Rocks) for a possible future San Mateo Rocks Lighthouse, and an act of Congress assigned ownership to the Bureau of Land Management in 1935,[7] but the lighthouse facility was never built.[5][4] In the early 1970s the waters around the rocks were a collection site for seaweed species in genus Gelidium for use in agar production.[8]

The rocks host a transient population of California sea lions.[9][10] Indigenous people may have used San Mateo Rocks as a pinniped hunting ground.[11] On one occasion this population of sea lions attracted a pod of orcas—quite uncommon in local waters—who used a clever pack-hunting technique to force the sea lions off the rock and into the water where they would be ready prey.[12] The rocks are a common destination for local dive boats.[13]

## References

[edit]

1. ^ U.S. Geological Survey Geographic Names Information System: San Mateo Rocks
2. ^ Rider, Fremont; Cooper, Frederik Taber (1925). Rider's California: a guide-book for travelers, with 28 maps and plans. New York: Macmillan.
3. ^ a b Engstrom, Wayne N. (2006). "Nineteenth Century Coastal Geomorphology of Southern California". Journal of Coastal Research. 22 (4): 847–861\. doi:10.2112/03-0025.1. ISSN 0749-0208. JSTOR 4300343. S2CID 128984180.
4. ^ a b Resources, United States Congress House Committee on Natural (2009). To Eliminate an Unused Lighthouse Reservation, Provide Management Consistency by Incorporating the Rocks and Small Islands Along the Coast of Orange County, California, Into the California Coastal National Monument Managed by the Bureau of Land Management, and Meet the Original Congressional Intent of Preserving Orange County's Rocks and Small Islands, and for Other Purposes: Report (to Accompany H.R. 86) (including Cost Estimate of the Congressional Budget Office). U.S. Government Printing Office.
5. ^ a b Furey, Donna (2017-01-20). "Obama Elevates Bird Rock's Status". Laguna Beach Local News. Retrieved 2023-04-09.
6. ^ "Santa Barbara Weekly Press 12 December 1907 — California Digital Newspaper Collection". cdnc.ucr.edu. Retrieved 2023-04-09.
7. ^ California Coastal History (PDF). pp. 3–27.
8. ^ "The Los Angeles Times 19 May 1974, page 291". Newspapers.com. Retrieved 2023-04-09.
9. ^ California (1914). California fish and game v.33-34 1947-1948. San Francisco, etc.: State of California, Resources Agency, Dept. of Fish and Game.
10. ^ University of California, Santa Cruz; United States (1978). Marine mammal and seabird survey of the Southern California Bight area. PB ; 295 934. Washington : Springfield, Va.: Dept. of the Interior, Bureau of Land Management ; for sale by the National Technical Information Service.
11. ^ Reddy, Seetha N.; Lev-Tov, Justin; Van Galder, Sarah; Ciolek-Torello, Richard (2015). "Fish Tales from the Ballona: The Role of Fish Along the Mainland Coast of Southern California". Journal of California and Great Basin Anthropology. 35 (2). ISSN 0191-3557.
12. ^ Swegles, Fred (2011-07-08). "Long-timers spin fishing tales of old O.C." Orange County Register. Retrieved 2023-04-09.
13. ^ "Disposition of Offshore Cooling Water Conduits February 21, 2005 4.4-1 SONGS Unit 1 EIR" (PDF). p. 4.4-7.

33°24′17″N 117°37′01″W﻿ / ﻿33.40472°N 117.61694°W﻿ / 33.40472; -117.61694