Although this may also be considered a foray into oyster husbandry, it is based on the public fishery rather than the private efforts undertaken in Virginia. In 1960, the state of Maryland started a repletion program based on shell deployment to maximize recruitment and support the oyster fishery (MacKenzie, 1997). Sieling, Maryland Department of Natural Resources, Annapolis, personal communication, 1994). From the 1920s to the 1950s, annual harvests from leased grounds were about 100,000 bushels, an insignificant amount when compared to landings from public fisheries (F. In Maryland waters only a small portion of the bottom is available for leasing, a total of 11,000 acres in 1892 and 12,000 acres in 1952 (MacKenzie, 1997). This may be considered a rudimentary oyster culture system, reliant on natural spatfall originating in public beds but based on private-sector initiative and investment. In the 1870s, Virginia oystermen established a system where they harvested seed from public grounds and transferred it to their leases to grow to market size. Maryland and Virginia adopted various approaches and priorities when landings began to decrease. In 1884, 615,000 tons of oysters were produced in Chesapeake Bay, around 20% of the current worldwide production (Goulletquer et al., 1994a). In Chesapeake Bay, vast stretches of prolific oyster grounds supported a large public fishery until the late 19th century, reducing the interest in developing aquaculture techniques. Advances in containment system design have facilitated the expansion of aquaculture into offshore waters (Goulletquer and Héral, 1997). Production of oyster seed in hatcheries has allowed greater control of reproductive output and initiated the use of selectively bred oyster strains. The most recent advance is the introduction of hatchery production in the 1980s (Jones and Jones, 1982 Chew, 1984). The development of new techniques for using spat collectors to control spat supply was key to the development of aquaculture production during the 19th and 20th centuries. However, the true development of oyster culture in Europe was initiated during the 18th century to sustain the harvest after increased fishing effort depleted the natural beds and fishing regulations failed to halt the precipitous decline in oyster landings. For instance, the Romans built ponds to stockpile the harvest and collected spat on wooden branches (Clark, 1964 Héral and Deslous-Paoli, 1991). Oyster culture has been practiced since ancient times. These statistics indicate a significant shift toward intensive aquaculture practices. In contrast, wild harvest fisheries produced 157,409 tons, mainly C. Based on statistics from the Food and Agriculture Organization (FAO), worldwide oyster production reached a record high of 4.3 million metric tons in 2000 4 million metric tons (93%) of those landings originated from aquaculture, of which 99.3% consisted of a single species, Crassostrea gigas (FAO, 2001).
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