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Does knowing the History of Life in the Bay help us with its Restoration?

Predicting the Future of San Francisco Bay: Learning from History. Does knowing the History of Life in the Bay help us with its Restoration?. Andrew Cohen Center for Research on Aquatic Bioinvasions. Reactive • Reducing Damage • Preservation Active • Restoration. Nichols et al. 1986.

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Does knowing the History of Life in the Bay help us with its Restoration?

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  1. Predicting the Future of San Francisco Bay: Learning from History Does knowing the History of Life in the Bay help us with its Restoration? Andrew Cohen Center for Research on Aquatic Bioinvasions

  2. Reactive • Reducing Damage • PreservationActive • Restoration

  3. Nichols et al. 1986

  4. Tidal Saltmarsh in San Francisco Bay Before 1850 190,000 acres 1979 31,000 acres 2000 40,000 acres Restoration target 100,000 acres

  5. Planting for saltmarsh restoration (from Zedler 1987).

  6. Paul Amato photo

  7. Eco-historical knowledge: • Past abundance • Why we lost it • Details of nature and function

  8. What does Eco-history tell us? Olympia oyster Ostrea lurida

  9. “Historically, the native oyster (Ostrea lurida), was present in the Bay in prodigious quantities.” —Skinner 1962 “Massive shell middens formerly found around the Bay indicated that aboriginal people consumed large quantities of mollusks, particularly the native oyster Ostrea lurida…Evidence of the rapid decline of shellfish resources soon after the arrival of the white man is equally striking.” —Nichols 1979 “These oysters were really super-abundant 150 years ago," said Edwin "Ted" Grosholz, a marine ecology specialist at UC Davis. “We know that from the harvest numbers in San Francisco Bay in the late 1800s...At one time, Olympia oysters littered San Francisco Bay.” —SF Chronicle 4/28/2003

  10. “Gold Rush settlers found the oysters irresistible and gobbled them up so fast they were just about harvested out of existence.” —Sacramento Bee 11/26/2001 “Over-harvesting and degraded water quality have depleted the native oyster (Ostrea lurida) population in San Francisco Bay, reducing a once dominant local fishery resource to a few scattered remnant populations.” —Save The Bay Summer 2001 “The vast reefs of the 1800s...were smothered by gold miners' silt, poisoned by raw sewage and carved up by Barbary Coast oystermen.” — SJ Mercury News 6/8/2004

  11. “In the past few years, researchers…began noticing an unfamiliar species...the native oyster of the bay, seldom seen since the 19th century. Apparently—and exactly how remains a mystery—the little native oyster hung on through the hard years of mining debris and low oxygen...in the bay.” —Booker 2006 Pacific Historical Review “The native Olympia oyster...once dominated San Francisco Bay’s ecosystem …Due to over harvesting, loss of habitat, and pollution, oysters virtually disappeared from the Bay…Indications that oysters were returning to San Francisco Bay were seen in the late 1990s when small, scattered populations were discovered on docks near Redwood City.” —submission to Journal of Shellfish Research

  12. • Abundant • Declined • Disappeared • Reappeared & Rediscovered 1700s to mid-1800s over-harvesting pollution mining sediment late 1800s-1900s 1990s Native Oysters in SFBay

  13. Front page part Front page of the San Francisco Chronicle, Feb. 4, 1999

  14. Presence of Native Oysters Redwood Creek to Vallejo year% of sitescommon at 1993 57% of 14 1 1994 77% of 13 1 1996 79% of 14 1 1997 75% of 12 2

  15. # of # of yearrecordsyearrecords 1951 3 1974 7 1962 2 1975 7 1963 2 1976 4 1964 2 1977 1 1970 5 1978 4 1971 1 1979 4 1973 4 Presence of Native Oysters 1951-1979

  16. Albatross Survey 1912-13

  17. Albatross dredge map • Native oysters collected at 17 sites.

  18. • Abundant • Declined • Disappeared • Reappeared & Rediscovered 1700s to mid-1800s over-harvesting pollution mining sediment late 1800s-1900s late 1990s Native Oysters in SFBay

  19. 1769 Portola 1776 Ayala & Anza 1834 Independence 1848 Gold 1850 Olympia oyster imported from Washington and reared in the Bay 1869 Virginia oyster imported from East Coast and reared in the Bay

  20. SF in 1847

  21. Population of San Francisco 1794 1,056 1798 833 1800 867 1815 1,488 1830 350 1842 196 1844 50 1846 200 1847 459 1848 850 1849 5,000 1850 21,000 1860 56,802 1870 149,473 1880 233,959 1890 298,997 1900 342,782

  22. Main Writings on the History of Oysters In California Barrett (1963) The California Oyster Industry Skinner (1962) Fish and Wildlife Resources of the San Francisco Bay Area Bonnot (1935) The California Oyster Industry Townsend (1893) Report of Observations Respecting the Oyster Resources and Oyster Fishery of the Pacific Coast of the United States Ingersoll (1881) The Oyster-Industry

  23. Estimated Depth of Sediment (m)Deposited from 1870-1896 Suisun Bay & Carquinez Strait 0.30 San Pablo Bay 0.47 Central Bay 0.00 South Bay -0.05 — based on Krone (1979)

  24. So if it wasn’t overharvesting,or pollution, or hydraulic mining debris that did in the native oysters,then what did?

  25. West Berkeley Shellmound

  26. SFChron-Front page.jpg from Story et al. 1966

  27. • Abundant • Declined • Disappeared • Reappeared & Rediscovered 1700s to mid-1800s over-harvesting pollution mining sediment late 1800s-1900s late 1990s Native Oysters in SFBay

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