Abstract We examined the effect of mesoscale oceanographic conditions on the seasonal abundance and distribution patterns of chaetognaths, a major component of the zooplankton community in the northern Gulf of Mexico, with data collected in late spring (May/June) and summer (July) from 2015 to 2017. Overall, 13 chaetognath species from six genera were observed in the samples. Significant pairwise associations were found between some species of chaetognaths, e.g. Flaccisagitta enflata and Sagitta bipunctata, which were affected by the distance of sampling stations to the Loop Current front. Flaccisagitta hexaptera observed in the samples appeared as an indicator species of high salinity water. Additionally, the abundance of chaetognaths showed an increasing trend as the distance increased from the Loop Current front. The potential effects of environmental factors (e.g. SST, salinity, and dissolved oxygen) and oceanographic features (i.e. the Loop Current front) on abundance and distribution of chaetognaths were further examined using non-metric multidimensional scaling (NMDS) and generalized additive models (GAM). The NMDS ordination showed significant differences in chaetognath assemblages between the cruises. Furthermore, the GAM modeling displayed species-specific impacts of salinity, dissolved oxygen, and distance to the Loop Current front on the abundance of key chaetognaths in the region. Given the critical roles of zooplankton communities, this three-year study of chaetognaths contributed to the understanding of the processes and drivers of zooplankton dynamics in relation to environmental factors in the northern Gulf of Mexico to further explore how these changes would affect fisheries production and ecosystem functions in the areas.

中文翻译：

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墨西哥湾北部毛颚动物的季节性丰度和分布：环流和密西西比河羽流的影响

摘要 我们研究了中尺度海洋条件对墨西哥湾北部浮游动物群落的主要组成部分毛颚类的季节性丰度和分布模式的影响，数据是在晚春（5 月/6 月）和夏季（7 月）从2015 年至 2017 年。总体而言，在样本中观察到来自 6 个属的 13 种毛颌物种。在某些毛颌物种之间发现了显着的成对关联，例如 Flaccisagitta enflata 和 Sagitta bipunctata，它们受到采样站到环流前沿的距离的影响。在样品中观察到的 Flaccisagitta 六翅目表现为高盐度水的指示物种。此外，随着距环流前沿的距离增加，毛颌的丰度呈增加趋势。使用非度量多维标度 (NMDS) 和广义加性模型 (GAM) 进一步检查了环境因素（例如 SST、盐度和溶解氧）和海洋学特征（即环流前沿）对毛颚动物丰度和分布的潜在影响）。NMDS 排序显示航行之间的毛颌组合存在显着差异。此外，GAM 模型显示了盐度、溶解氧和到环流前沿的距离对该地区主要毛颚动物丰度的物种特异性影响。鉴于浮游动物群落的关键作用，