Seasonal distributions and predicting migratory pathways for three species of bats

Understanding seasonal variation in the distribution and movement patterns of migratory species is essential to monitoring and conservation efforts. While there are many species of migratory bats in North America, little is known about their seasonal movements. In terms of conservation, this is important because the bat fatalities from wind energy turbines are significant and may fluctuate seasonally. Here we describe seasonally resolved distributions for the three species that are most impacted by wind farms (Lasiurus borealis [eastern red bat], L. cinereus [hoary bat], and Lasionycteris noctivagans [silver-haired bat]) and use these distributions to infer their most likely migratory pathways. To accomplish this, we collected 2880 occurrence points from the Global Biodiversity Information Facility over five decades in North America to model species distributions on a seasonal basis and used an ensemble approach for modeling distributions. This dataset included 1,129 data points for L. borealis, 917 for L. cinereus, and 834 for L. noctivagans. The results suggest that all three species exhibit variation in distributions from north to south depending on season, with each species showing potential migratory pathways during the fall migration that follow linear features.  Finally, we describe proposed migratory pathways for these three species that can be used to identify stop-over sites, assess small-scale migration and highlight areas that should be prioritized for actions to reduce the effects of wind farm mortality.

解析迁徙物种的分布与活动模式的季节变化，对于物种监测与保护工作至关重要。北美分布着诸多迁徙蝙蝠物种，但学界对其季节性迁徙活动的认知仍较为匮乏。从保护视角而言，这一现状意义重大：风能涡轮机导致的蝙蝠死亡数量可观，且该数值可能随季节发生波动。
本研究针对受风力发电厂影响最严重的三个蝙蝠物种：东部红蝠（Lasiurus borealis, eastern red bat）、灰蓬毛蝠（Lasiurus cinereus, hoary bat）以及银毛蝠（Lasionycteris noctivagans, silver-haired bat），刻画了其分季节的分布格局，并基于此推演三者最可能的迁徙路径。为完成上述研究，我们从全球生物多样性信息设施（Global Biodiversity Information Facility, GBIF）收集了北美地区50余年间的2880条物种出现记录，以分季节的方式构建物种分布模型，并采用集成建模方法开展分布模拟。该数据集包含东部红蝠记录1129条、灰蓬毛蝠记录917条以及银毛蝠记录834条。
研究结果显示，三个物种的南北分布格局均随季节发生显著变化，且三者在秋季迁徙期间均呈现出沿线性地貌开展迁徙的潜在路径。最后，本研究提出了上述三个物种的迁徙路径方案，可用于识别中途停歇地、评估局地迁徙情况，并明确需优先开展风电致死影响消减行动的区域。