Variability in mesopelagic fish assemblages of the deep-scattering layer were explored in relation to mesoscale anticyclonic (warm-core) eddies in the western North Atlantic Ocean. Exploratory fishing with a mid-water herring trawl was combined with oceanographic sampling aboard the RV Celtic Explorer in the Spring of 2015 and 2016 to characterize mesopelagic fish assemblages along transects through anticyclonic eddies identified using real time satellite-derived sea level anomaly. Sampling yielded a total of 6087 fish specimens, representing at least 109 species across 38 families. The families Myctophidae and Stomiidae were the most speciose taxa sampled and comprised >50% of total catch abundance in each year. Species richness and diversity (H’) were significantly higher in sets occurring inside relative to outside the eddy structures. Community analyses indicate significant differences in daytime assemblage structure between both depth groups (shallow 200–400 m versus deep 400–700 m) and eddy groups (inside versus outside), with ordination discrimination of 5 pelagic fish assemblages related to eddy groups. Anticyclonic eddies also harbored more juveniles and rare species, including species with more southerly distributions within the Gulf Stream. Our results indicate anticyclonic eddies may play an important role in structuring fish assemblages and the dispersion of mesopelagic species in the Northwest Atlantic.

研究了北大西洋西部中尺度反旋流（暖芯）涡旋与深散射层的近古鱼类组合的变化性。在RV Celtic Explorer上，利用中层鲱鱼拖网进行的探索性钓鱼与海洋采样相结合在2015年的春季和2016年的春季，通过反旋风涡旋来确定沿样带的中古生鱼群的特征，这些旋涡旋涡是使用实时卫星衍生的海平面异常来识别的。采样共采集了6087条鱼标本，代表了38个科中的至少109种。Myctophidae和Stomiidae家族是最特殊的分类单元，每年占总捕捞量的50％以上。相对于外部涡流结构，内部富集的物种丰富度和多样性（H'）显着更高。社区分析表明，两个深度组（浅200–400 m与深400–700 m）和涡流组（内部与外部）之间的白天组合结构存在显着差异，并与5个与涡流组相关的浮游鱼类组合进行了区分。反气旋涡也包含更多的幼年和稀有物种，包括在墨西哥湾流中向南分布的物种。我们的研究结果表明，反气旋涡旋可能在构造鱼类组合以及中大西洋近中生物种的扩散方面起着重要作用。