Study of Oyster Growth and Population Structure in San Antonio and Espiritu Santo Bays-Survey of Oyster Populations and Associated Organisms


Beginning in July, serious oyster mortalities occurred in central and lower San Antonio Bay. Although losses among market oysters were most severe, the smaller seed oysters were also affected. By the end of the year, almost all of the oysters in central San Antonio Bay were dead. The organism responsible for such mortalities was not determined. Since the incidence of the oyster parasite, Dermocystidium marinum, was low during the mortality period, it was not considered to be a primary causative agent. The mortality was not observed in Espiritu Santo Bay or in the southwestern portion of San Antonio Bay. Spat setting and survival appeared to be good and a general increase in the number of oysters was observed in samples in these two areas by the end of the year. Commercial oyster production during the 1962-63 season was confined to San Antonio Bay north of the Intra-Coastal Waterway. No production was reported from Espiritu Santo Bay. During the initial months of the 1963-64 season, all production was confined to north-central San Antonio Bay and to the western bay shore. The legal size limit was reduced to three inches. In December, an outbreak of "red" oysters occurred in local shucking plants. After eight to ten days in cold storage the packaged oysters became red in color. The causative agent was presumed to be a yeast.


pages 213-222; available for download at the link below.


'red" oysters, oysters, oyster mortality, stock assessment