CURRENT STATUS OF THE CALIFORNIA OYSTER INDUSTRY

The oyster culture operation in Moro Bay is typical of the United States Pacific Coast Crassostrea gigas mariculture industry. Of this Bay's 1,000 hectares of marshes, tidelands and channels 400 hectares have been alloted by the State of California for private oyster cultivation. Approximately 180 hectares of this allotment are suitable for bottom and stake culture on a three-year growing cycle. Each year this 60 hectares is planted with cultch shell at the rate of 60 cases of cultch per hectare. Each case contains an average of 1,000 cultch shells with 10 oyster spat per shell. A typical survival rate of 30% yields, 3,000 liters of oyster meat per hectare after 36 months of growth. The history of the California oyster industry and the start of mariculture in the state began in San Francisco following the discovery of gold. Along with the quest to strike it rich, the easterners also brought an appetite for their east coast favorite, the eastern oyster, Crassostrea virginica. BARRETT (1963) reported that attempts were first made to bring this eastern species to San Francisco both fresh and preserved, but evidently the few successful shipments could not satisfy the California market. In the 1850's the native Pacific oyster, Ostrea lurida was shipped from Shoalwater Bay (now Willapa), Washington, to San Francisco (BARRETT 1963). This Shoalwater source supplied the greatest part of the San Francisco market, yet a number of other locations in Oregon (Yaquina and Netart's Bays) and Washington's Puget Sound were harvested (HITTELL 1882). BARRETT (1963) indicates that while the oysters were initially sold wholesale and retail, the industry, with its increased size, began organizing and started the practice of holding oysters on suitable mudflats in San Francisco Bay until needed. The completion of the transcontinental railroad linking San Francisco to the east coast marked a time of change in the Pacific coast oyster industry (BARRETT 1963). BARRETT (1963) reported that eastern oysters were immediately imported and soon the Washington source became insignificant. This involved, in addition to adults, the importation of baby (seed) oysters, and marked the beginning of relatively independent oyster production. At Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA. 93407. 115 Mar. Res. Indonesia Vol.20, 1977: 115-130 DOI: 10.14203/mri.v20i0.386 THOMAS L. RICHARDS & PHILLIP R. TAYLOR this period BARRETT (1963) reports that the major drawback to sustained mariculture was the inability of the introduced oysters to reproduce in California waters, resulting in a continued need for seed oysters. BARRETT (1963) indicates that this seed mariculture was quite profitable in San Francisco in 1875, and continued to be so past the turn of the century at which time a noticeable decline began. There has been speculation that reports of pollution (EBERT 1973, FREY 1 9 7 1 ) and consequent fear of contaminated oysters played a part in this period of decline, but eventually oysters failed to mature and survive in the Bay (BARRETT 1963). The importation of mature eastern oysters increased as did the imports from Washington (BARRETT 1963). While San Francisco was the center of the organized oyster industry, San Diego, Tomales and Humboldt Bays were approached with varying degrees of success. San Diego Bay was proposed as a location to be involved in the importation of Mexican oysters (BARRETT 1963). The idea was to use the bay for freshening Mexican oysters on their way up to San Francisco (INGERSOLL 1881). TOWNSEND (1893) reported an attempt at raising easterns in San Diego Bay but apparently with no success. Tomales Bay was first used for rearing eastern oysters in 1875 (TOWNSEND 1893) but this effort ceased until the decline of the San Francisco Bay industry (BARRETT 1963). The early industry at Tomales Bay involved seed and full-grown eastern oysters as well as native Olympic oysters (Ostrea lurida) from Washington (BARRETT 1963). Humboldt Bay's early encounters with the culture of oysters fell to failure. In the late 19th century the U.S. Bureau of Fisheries made an unsuccessful attempt at raising oysters and later in the early 1900's the oysters translocated from the failing San Francisco beds met with similar lack of success (BARRETT 1963). In 1902 the Pacific oyster, Crassostrea gigas was introduced to the waters of Washington (GALTSOFF 1932) from Japan, and in 1905 commercial mariculture of this species began (BARRETT 1963). Due to lower costs, lower mortalities, and fine success in its growth, the Pacific oyster has become the principle species of the west coast oyster industry in the U.S. (BARRETT 1963). It was not, however, until the late 1920's and early 1930's that commercial interest in the Pacific oyster in California got started (BONNOT 1935, BARRETT 1963, FREY 1971, EBERT 1973). The Tomales Bay Oyster Company made the initial experimental plantings in 1928 (BARRETT 1963) and in 1929 plantings of seed were made in Elkhorn Slough (BONNOT 1935). The major factor hampering the industry was the dependence on seed oyster imports as Crassostrea gigas, like C. virginica, does not successfully reproduce in the cold California waters (BARRETT 1963, FREY 1971). As a conse116 Mar. Res. Indonesia Vol.20, 1977: 115-130