The species occurrence of mesopelagic fish collected in the scattering layers was studied across the Indian Ocean subtropical gyre during the dry season (2015). Ocean eddies can retain zooplankton and plastic debris, and determine biological composition through advection. The conditions inside the gyre were stabilised by low chlorophyll-a concentrations and a deep nutricline. A diverse assemblage of mesopelagic fish, dominated by myctophids, exhibited diel migrations to the upper water layers for feeding since the early night. Myctophids were concentrated ca. 100 m depth, where the deep chlorophyll maximum was located, and coinciding with the nutricline. Another group of mesopelagic fish remained in deeper waters during the daytime, with a higher occurrence of Stomiiformes (Phoshycthyidae and Sternoptychidae) at the 500–600 m Deep Scattering Layer. Moreover, the diets of 220 myctophid specimens belonging to the species Ceratoscopelus warmingii, Diaphus effulgens, and Symbolophorus evermanni, were investigated based on stomach content analysis. Calanoid copepods, mainly Pleuromamma abdominalis, made up 30% of the diet in the three myctophid species, with interspecific differences in the preferred second item: C. warmingii preferred ostracods, D. effulgens, non-calanoid copepods, and S. evermanni, euphausiids. Thus, partial dietary segregation was observed among the three species. We hypothesized that these myctophid diets differed between stations located at the gyre core and its outer edge. Any dietary pattern indicating aggregation of food resources, or an enhancement of the foraging opportunities for myctophids, was discerned as an effect of the gyre advection. However, prey composition diverged between the core and the outer edge stations regardless of the fish species, with a higher dietary representation of P. abdominalis and euphausiids (migratory zooplankton) in the individuals collected in the core-influenced area. A total of six plastic pieces were present in the stomachs of D. effulgens and S. evermanni, in contrast with the high presence of plastic particles found at the surface in most sampling stations (average number of plastic pieces was 41 per hour). The selected myctophid species did not appear to be important transport vectors for microplastics in comparison with species from other oceans.

在干旱季节（2015年），研究了印度洋亚热带回旋带中散射层收集的中生鱼类的物种发生。海洋涡流可以保留浮游动物和塑料碎片，并通过平流确定生物成分。低叶绿素a浓度和深营养可稳定回旋内部的状况。自深夜以来，各种不同的中生鱼类组成，其中以线粒体为主，表现出diel迁移到上层水层进行觅食。Myctophids被浓缩约。深度为100 m，最深的叶绿素位于该位置，与营养素重合。白天，另一群中生鱼类保留在深水区，在500-600 m的深层散射层中，甲状纲（Phhyhycythyidae和Sternoptychidae）的发生率较高。此外，属于物种220个myctophid标本饮食Ceratoscopelus warmingii，Diaphus effulgens，和Symbolophorus evermanni，根据胃内容分析进行了调查。哲水蚤桡足类，主要Pleuromamma腹，在三个myctophid物种由30％的饮食，具有在优选的第二项的种间差异：C. warmingii优选介形类，D. effulgens，非-足类co足类动物和S. evermanni，长足类动物。因此，在这三个物种中观察到部分饮食隔离。我们假设这些绕线虫的饮食在位于回旋核心及其外缘的站点之间是不同的。可以看出，任何指示食物资源聚集的饮食模式，或增加了食丝虫的觅食机会，都是旋流平流的影响。但是，无论鱼类种类如何，猎物的组成在核心站和外缘站之间都不同，在核心影响区收集的个体中，腹地疟原虫和e虾（迁徙的浮游动物）的饮食代表性较高。D. effulgens的胃中总共有六个塑料块和S. evermanni相比，在大多数采样站中表面上发现的塑料颗粒数量很高（塑料片的平均数量为每小时41个）。与来自其他海洋的物种相比，所选的Myctophid物种似乎不是微塑料的重要运输媒介。