Investigation on the acoustic scattering signatures of Copepods-The first step to conducting acoustic survey on copepods-

研究了海洋浮游动物中数量最多的桡足类动物的声散射特性（Target Strength: TS）。在海水中测量桡足类动物的TS，并通过测量声学参数，利用理论模型进行估算。比较两种TS。结果证实，TS估计值与一些个体的实际测量值很好地匹配，而与另一些个体完全不同。研究发现，前者个体体内没有油囊，后者个体体内有油囊。我们将进一步详细研究这种差异。

Properties of the animal's acoustic scattering(Target Strength : TS) were investigated in copepods which have the highest population among zooplanktons living in the ocean. TS of copepods were measured in a sea-water tank, and estimated using the theoretical model by measuring the acoustic parameters. Both TS were compared. As a result, it was confirmed that TS estimates matched the actual measurements of some individuals well while entirely differed with other individuals. When the differences were investigated, it was found that the former individuals did not have oil sac into the copepods body while the latter individuals had oil sac. We will further investigate this difference in detail.