Abstract Apherusa glacialis is a common, sea ice-associated amphipod found throughout the Arctic Ocean and has long been considered permanently associated with the sea ice habitat. However, pelagic occurrences of A. glacialis have also been reported. It was recently suggested that A. glacialis overwinters at depth within the Atlantic-water inflow near Svalbard, to avoid being exported out of the Arctic Ocean through the Fram Strait. This study collated pelagic occurrence records over a 71-year period and found that A. glacialis was consistently found away from its presumed sea ice habitat on a pan-Arctic scale, in different depths and water masses. In the Svalbard region, A. glacialis was found in Atlantic Water both in winter and summer. Additionally, we analyzed A. glacialis size distributions throughout the year, collected mostly from sea ice, in order to elucidate potential life cycle strategies. The majority of young-of-the-year A. glacialis was found in the sea ice habitat during spring, supporting previous findings. Data on size distributions and sex ratios suggest a semelparous lifestyle. A synchronous seasonal vertical migration was not evident, but our data imply a more complex life history than previously assumed. We provide evidence that A. glacialis can no longer be regarded as an autochthonous sympagic species.

中文翻译：

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整个北极冰片脚类动物 Apherusa glacialis 的远洋事件

摘要 Apherusa glacialis 是一种常见的、与海冰相关的片脚类动物，在整个北冰洋发现，长期以来一直被认为与海冰栖息地有永久联系。然而，A. glacialis 的远洋事件也有报道。最近有人建议，A. glacialis 在斯瓦尔巴群岛附近的大西洋水流入的深处越冬，以避免通过弗拉姆海峡输出到北冰洋之外。这项研究整理了 71 年间的远洋发生记录，发现 A. glacialis 一直被发现远离其假定的海冰栖息地，在泛北极范围内，在不同深度和水团中。在斯瓦尔巴群岛地区，冬季和夏季都在大西洋水域发现了 A. glacialis。此外，我们分析了 A. glacialis 全年的大小分布，主要从海冰中收集，以阐明潜在的生命周期策略。大多数年幼的 A. glacialis 是在春季的海冰栖息地中发现的，这支持了之前的发现。大小分布和性别比例的数据表明了一种半产的生活方式。同步季节性垂直迁移并不明显，但我们的数据意味着比以前假设的更复杂的生活史。我们提供的证据表明 A. glacialis 不能再被视为本土的交感物种。但我们的数据意味着比以前假设的更复杂的生活史。我们提供的证据表明 A. glacialis 不能再被视为本土的交感物种。但我们的数据意味着比以前假设的更复杂的生活史。我们提供的证据表明 A. glacialis 不能再被视为本土的交感物种。