We examined the feeding habits of the dominant mesopelagic fish Sigmops gracilis larvae across the Kuroshio Current, southern Japan. The feeding incidence tended to decrease toward the offshore area. Copepods, amphipods, ostracods, and appendicularians were microscopically observed in the guts. Larvae fed substantially on copepods such as calanoids and appendicularians. Appendicularians were more frequently ingested toward the offshore area and were the most preferential prey item in all areas. The microbial production integrated by appendicularians would support mesopelagic fish larvae in addition to the ordinary trophic pathway through copepods.

中文翻译：

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日本南部黑潮及其邻近水域中远洋鱼 Sigmops gracilis 幼虫的摄食习性

我们研究了日本南部黑潮中占主导地位的中层鱼类 Sigmops gracilis 幼虫的摄食习性。摄食发生率趋向于向近海地区减少。在肠道中显微镜观察到桡足类、片脚类、介形类和附肢类。幼虫主要以桡足类动物为食，如海藻和附肢动物。附肢更频繁地被摄入到近海区域，并且是所有区域中最优先的猎物。除了通过桡足类动物的普通营养途径外，附肢动物整合的微生物生产还将支持中层鱼类幼虫。