Changes in environmental conditions can have strong energetic effects on animals through limited food availability or increased thermoregulatory costs. Especially difficult are periods of increased energy expenditures, such as reproduction. Reproductive female bats from the temperate zone often aggregate in maternity colonies to profit from social thermoregulation to reduce torpor use and buffer the effects of poor conditions. The much rarer male colonies may form for similar reasons during testes development. Male colonies thus allow us to study the influence of environmental conditions on energy budget and colony size, without the confounding effects of parental care. We remotely monitored skin temperature and assessed colony size of male parti-coloured bats Vespertilio murinus during summer, and correlated those variables with environmental conditions and food availability (i.e. insect abundance). As we had hypothesized, we found that colony size increased at colder temperatures, but decreased at low wind speeds. Also as predicted, torpor use was relatively low, however, it did increase slightly during adverse conditions. Male sociality may be an adaptation to adverse environmental conditions during sexual maturation, but the pressure to avoid torpor during spermatogenesis may be lower than in pregnant or lactating females.

中文翻译：

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雄性蝙蝠以更大的群体和在精子生产过程中增加麻木的使用来应对不利条件

环境条件的变化可以通过有限的食物供应或增加的体温调节成本对动物产生强烈的能量影响。特别困难的是能量消耗增加的时期，例如繁殖。来自温带地区的繁殖雌性蝙蝠经常聚集在母性群体中，以从社会体温调节中获利，以减少麻木的使用并缓冲恶劣条件的影响。在睾丸发育过程中，可能会出于类似的原因形成少得多的雄性集落。因此，雄性菌落使我们能够研究环境条件对能量预算和菌落大小的影响，而没有父母照顾的混杂影响。我们在夏季远程监测皮肤温度并评估雄性杂色蝙蝠 Vespertilio murinus 的群体大小，并将这些变量与环境条件和食物供应（即昆虫丰度）相关联。正如我们假设的那样，我们发现菌落大小在较冷的温度下增加，但在低风速下减少。同样正如预测的那样，麻木的使用率相对较低，但在不利条件下确实略有增加。男性社会性可能是性成熟期间对不利环境条件的适应，但在精子发生期间避免麻木的压力可能低于怀孕或哺乳期的女性。