• Journal of Aquaculture
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• v.16 no.4
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• pp.229-232
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• 2003

Survival with various conditions (water temperature, salinity and air exposure) and sand immersion ability for release of surf clam, Spisula sachalinensis spats, which were artificially seed produced, were investigated. Survival with water temperature conditions of spats showed no difference within the range of 4∼28 $^{\circ}C$ for 10 days. In salinity conditions, survival (%) of spats showed more than 50% in over 22 psu. In air exposure conditions, survival (%) of spats air exposed for 12 hours was no difference within below 2$0^{\circ}C$, however, that of spats air exposed for 16 hours showed below 50% at $25^{\circ}C$. In sand immersion ability, the immersion time was increased with the increase of shell length, and the immersion rate was decreased. Spats of below 15 mm in shell length were emersed more than 90% within 10 min. There was no difference in the immersion time and the immersion rate with the grain sizes of the sand bottom.

• Journal of Aquaculture
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• v.20 no.2
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• pp.127-131
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• 2007

In order to obtain the basic biological data for effective seed production of Protothaca jedoensis, the influence of sediment condition on its immersion rate was investigated. Immersion rate of P. jedoensis spats was investigated in the different substrate groups; mud, fine sand, medium sand and coarse. In 72 hours, immersion rate and survival rate of spat was 90.0 and 90.0, 76.7 and 98.3, 61.7 and 86.7, and 85.0 and 93.3%, respectively. And also, survival rates of the groups were 90.0%(mud), 98.3%(fine sand), 86.7% (medium sand) and 93.3% (coarse sand) respectively. The immersion time and rate of spat was increased with an increase in shell length.