A study on food and feeding habit of the clam spat.
In trials, larvae and spat of clam (Ruditapes philippinarum) were offered planktonic and benthic unicellular algae. The spat grew normally. Those given a mixture of benthic diatoms and Chaetoceros sp. grew faster, 33.7 μm daily, with a higher rate of survival, about 80%, than those on other diets. Results were good with a mixture of Dicrateria zhanjiangensis and Chaetoceros sp., growth 29.2 μm daily and survival about 80%. Density of the feed organism was important; a density of 25 000 to 50 000 cells/ml was suitable for single or mixed feed species. Live Platymonas sp. was very active and difficult for bottom-living spat to catch, so frozen or heated cells were used in the trials. Results were better with frozen Platymonas. Other factors such as temperature, salinity and bottom soil may affect survival of the spat and should be considered.