The Arctic is currently experiencing the most rapid warming on Earth. Arctic species communities are expected to be restructured with species adapted to warmer conditions spreading poleward and, if already present, becoming more abundant. We tested this prediction using long-term monitoring data (2009–2018) from nine of the most common seabird species breeding in the High Arctic Svalbard archipelago. This region is characterized by rapidly warming ocean temperatures, declining sea-ice concentrations and an increasing influence of Atlantic waters. Concurrent with these environmental changes, we found a shift in the Svalbard seabird community, with an increase in abundance of boreal species (defined here as species breeding commonly in temperate environments) and a decline in Arctic species (species breeding predominantly in the Arctic). Combined with previous observations from lower trophic levels, our results confirmed that part of the Arctic fauna is moving from an arctic to a boreal (or north temperate) state, a process referred to as a “borealization.” Spatial variations exist among colonies for some species, indicating that local conditions may affect the trajectories of specific populations and potentially counterbalance the consequences of large-scale climate warming.

中文翻译：

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随着北极变得北半球：高北极海鸟群落的持续变化

北极目前正在经历地球上最迅速的变暖。北极物种群落预计将进行重组，物种适应更温暖的条件，向极地传播，如果已经存在，将变得更加丰富。我们使用长期监测数据（2009-2018 年）测试了这一预测，这些数据来自在高北极斯瓦尔巴群岛繁殖的九种最常见的海鸟物种。该地区的特点是海洋温度迅速升高、海冰浓度下降以及大西洋水域的影响越来越大。在这些环境变化的同时，我们发现斯瓦尔巴海鸟群落发生了变化，北方物种（这里定义为通常在温带环境中繁殖的物种）数量增加，而北极物种（主要在北极繁殖的物种）数量减少。结合先前在较低营养级的观察结果，我们的结果证实，部分北极动物群正在从北极迁移到北方（或北温带）状态，这一过程被称为“北极化”。某些物种的种群之间存在空间差异，这表明当地条件可能会影响特定种群的轨迹，并可能抵消大规模气候变暖的后果。