Newman Blaise A, Loeb Susan C, Jachowski David S
Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
USDA Forest Service, Southern Research Station, 233 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
Conserv Physiol. 2024 Apr 16;12(1):coae014. doi: 10.1093/conphys/coae014. eCollection 2024.
Many hibernating bats in thermally stable, subterranean roosts have experienced precipitous declines from white-nose syndrome (WNS). However, some WNS-affected species also use thermally unstable roosts during winter that may impact their torpor patterns and WNS susceptibility. From November to March 2017-19, we used temperature-sensitive transmitters to document winter torpor patterns of tricolored bats () using thermally unstable roosts in the upper Coastal Plain of South Carolina. Daily mean roost temperature was 12.9 ± 4.9°C SD in bridges and 11.0 ± 4.6°C in accessible cavities with daily fluctuations of 4.8 ± 2°C in bridges and 4.0 ± 1.9°C in accessible cavities and maximum fluctuations of 13.8 and 10.5°C, respectively. Mean torpor bout duration was 2.7 ± 2.8 days and was negatively related to ambient temperature and positively related to precipitation. Bats maintained non-random arousal patterns focused near dusk and were active on 33.6% of tracked days. Fifty-one percent of arousals contained passive rewarming. Normothermic bout duration, general activity and activity away from the roost were positively related to ambient temperature, and activity away from the roost was negatively related to barometric pressure. Our results suggest ambient weather conditions influence winter torpor patterns of tricolored bats using thermally unstable roosts. Short torpor bout durations and potential nighttime foraging during winter by tricolored bats in thermally unstable roosts contrasts with behaviors of tricolored bats in thermally stable roosts. Therefore, tricolored bat using thermally unstable roosts may be less susceptible to WNS. More broadly, these results highlight the importance of understanding the effect of roost thermal stability on winter torpor patterns and the physiological flexibility of broadly distributed hibernating species.
许多在温度稳定的地下栖息地冬眠的蝙蝠因白鼻综合征（WNS）数量急剧下降。然而，一些受WNS影响的物种在冬季也会使用温度不稳定的栖息地，这可能会影响它们的蛰伏模式和对WNS的易感性。在2017年11月至2019年3月期间，我们使用对温度敏感的发射器记录了南卡罗来纳州沿海平原上游使用温度不稳定栖息地的三色蝙蝠（ ）的冬季蛰伏模式。桥梁中每日平均栖息地温度为12.9±4.9°C（标准差），可进入的洞穴中为11.0±4.6°C，桥梁中每日波动为4.8±2°C，可进入的洞穴中为4.0±1.9°C，最大波动分别为13.8°C和10.5°C。平均蛰伏期持续时间为2.7±2.8天，与环境温度呈负相关，与降水量呈正相关。蝙蝠保持着集中在黄昏附近的非随机觉醒模式，在33.6%的追踪天数内活跃。51%的觉醒包含被动复温。常温期持续时间、一般活动和离开栖息地的活动与环境温度呈正相关，离开栖息地的活动与气压呈负相关。我们的结果表明，环境天气条件会影响使用温度不稳定栖息地的三色蝙蝠的冬季蛰伏模式。在温度不稳定栖息地的三色蝙蝠冬季蛰伏期持续时间短以及可能的夜间觅食与在温度稳定栖息地的三色蝙蝠行为形成对比。因此，使用温度不稳定栖息地的三色蝙蝠可能对WNS的易感性较低。更广泛地说，这些结果凸显了了解栖息地热稳定性对冬季蛰伏模式的影响以及广泛分布的冬眠物种生理灵活性的重要性。
