Data from: Geographic origins and population genetics of bats killed at wind-energy facilities

An unanticipated impact of wind-energy development has been large-scale mortality of insectivorous bats. In eastern North America, where mortality rates are among the highest in the world, the hoary bat (Lasiurus cinereus) and the eastern red bat (L. borealis) comprise the majority of turbine-associated bat mortality. Both species are migratory tree bats with widespread distributions; however, little is known regarding the geographic origins of bats killed at wind-energy facilities or the diversity and population structure of affected species. We addressed these unknowns by measuring stable hydrogen isotope ratios (δ2H) and conducting population genetic analyses of bats killed at wind-energy facilities in the central Appalachian Mountains (USA) to determine the summering origins, effective size, structure, and temporal stability of populations. Our results indicate that ~1% of hoary bat mortalities and ~57% of red bat mortalities derive from non-local sources, with no relationship between the proportion of non-local bats and sex, location of mortality, or month of mortality. Additionally, our data indicate that hoary bats in our sample consist of an unstructured population with a small effective size (Ne) and either a stable or declining history. Red bats also showed no evidence of population genetic structure, but in contrast to hoary bats, the diversity contained in our red bat samples is consistent with a much larger Ne that reflects a demographic expansion after a bottleneck. These results suggest that the impacts of mortality associated with intensive wind-energy development may affect bat species dissimilarly, with red bats potentially better able to absorb sustained mortality than hoary bats because of their larger Ne. Our results provide important baseline data and also illustrate the utility of stable isotopes and population genetics for monitoring bat populations affected by wind-energy development.

风电开发带来了一项始料未及的影响：食虫蝙蝠出现大规模死亡。在死亡率位居全球前列的北美东部地区，灰蝠（Lasiurus cinereus）与东方红蝠（L. borealis）占风力涡轮机相关蝙蝠死亡事件的绝大多数。这两个物种均为分布广泛的迁徙性树栖蝙蝠，但学界对于风电设施致死蝙蝠的地理起源，以及受影响物种的多样性与种群结构仍知之甚少。为此，本研究通过测定美国阿巴拉契亚山脉中部风电设施致死蝙蝠的稳定氢同位素比值（δ²H），并开展种群遗传分析，以明确种群的夏季起源、有效种群大小（Ne）、结构及时间稳定性。研究结果显示，约1%的灰蝠死亡个体与约57%的东方红蝠死亡个体均来自非本地种群，且非本地蝙蝠的占比与蝙蝠性别、死亡地点或死亡月份均无关联。此外，本次样本中的灰蝠种群无遗传结构分化，有效种群大小（Ne）较小，种群历史或趋于稳定，或呈下降趋势。东方红蝠同样未表现出种群遗传结构分化，但与灰蝠不同的是，本研究中东方红蝠样本的遗传多样性与更大的有效种群大小相符，这反映出其种群在经历瓶颈效应后发生了扩张。上述结果表明，规模化风电开发带来的致死效应对不同蝙蝠物种的影响存在差异：由于东方红蝠拥有更大的有效种群大小，其或许比灰蝠更能耐受持续的蝙蝠死亡事件。本研究结果不仅提供了重要的基线数据，同时也证明了稳定同位素与种群遗传学方法在监测受风电开发影响的蝙蝠种群方面的应用价值。