• The Korean Journal of Malacology
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• v.27 no.3
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• pp.199-204
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• 2011

We studied possibility of the sowing culture at the bottom after intermediate culture as a method for raising the survival of the Purplish Washington clam, Saxidomus purpuratus. The pearl net ($35cm(W){\times}35cm(B){\times}20cm(H)$) for S. prupuratus spat during the period of intermediate culture (hanging culture) from April to October in 2010. The pearl net (100 inds./net) was installed at two stations (Namhae and Pohang) being about 3-4 m in water depth. After hanging culture, S. prupuratus spat sowed in the bottom of the Gangjin Bay. The survivals (%) of intermediate culture of this species at Namhae station and Pohang station were 73% and 74%, respectively. Daily growth rate of mean shell length and mean weight in Namhae station were higher than those in Pohang station. After sowing at the bottom of the Gangjin Bay, its survival (%) showed 73.98% in January 2011. These results suggested the possibility of the intermediate culture as hanging culture for raising survival rate of S. prupuratus.

• The Korean Journal of Malacology
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• v.26 no.4
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• pp.261-265
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• 2010

Reproductive biology of the purplish Washington clam, Saxidomus purpuratus was investigated based on the samples captured in Jinhae Bay, the East China Sea from January to December 2002. The gonad index (GI) began to increase in January, reached the maximum value in March. The reproductive cycle of this species can be divided into five successive stages: the early active stage (from November to January), the late active stage (from December to February), the ripe stage (from February to May and October), the spawned stage (from May to December), and inactive stage (from November to December). The spawning period was from April to December, and the main spawning occurred between June and August. The shell length at 50% group maturity was estimated to be 71.85 mm. The Sex ratio of this species was not significantly different a 1:1 sex ratio (P > 0.05).