Animal behaviour can affect individual fitness and is influenced by exogenous and endogenous factors. Here, we investigated how light (daylight length and moonlight), weather (precipitation and temperature), age, sex and social status affected activity and movement of a semiaquatic mammal, the Eurasian beaver (Castor fiber), using GPS relocation data from 47 individuals in south-eastern Norway. Independent of daylight length, beavers had a mean daily activity time of 9:42 h and reduced their activity periods when they were older, most likely due to senescence. In line with this, older individuals also spent less time in water and moved shorter distances. Furthermore, beavers reduced their activity periods in drier weather conditions and spent less time on land during brighter nights and drier conditions, indicating a predation risk avoidance strategy. Individuals spent less time in the water during the colder parts of the year and moved shorter distances with decreasing temperature, suggesting thermal constraints. Our study adds to the increasing amount of evidence that animal behaviour is modulated by various endogenous and exogenous factors, and that weather conditions can affect their behaviour. It remains to be tested, however, how climate variability together with hunting and predation pressure affect space use and demography in species such as the Eurasian beaver.

中文翻译：

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海狸（蓖麻纤维）活动和空间运动响应光线和天气条件

动物行为会影响个体适应性，并受外源和内源因素的影响。在这里，我们使用来自 47 个人的 GPS 重定位数据调查了光（日光长度和月光）、天气（降水和温度）、年龄、性别和社会地位如何影响半水生哺乳动物欧亚海狸（蓖麻纤维）的活动和运动在挪威东南部。与日光长度无关，海狸的平均每日活动时间为 9:42 小时，并且随着年龄的增长而减少活动时间，这很可能是由于衰老。与此一致的是，老年人在水中的时间也更少，移动的距离也更短。此外，海狸在较干燥的天气条件下减少了活动时间，并在较亮的夜晚和较干燥的条件下减少了在陆地上的时间，表明捕食风险规避策略。在一年中较冷的部分，人们在水中呆的时间更少，并且随着温度的降低移动的距离更短，这表明热限制。我们的研究增加了越来越多的证据，表明动物行为受各种内源性和外源性因素的调节，并且天气条件会影响它们的行为。然而，气候变化以及狩猎和捕食压力如何影响欧亚海狸等物种的空间利用和人口统计仍有待测试。我们的研究增加了越来越多的证据，表明动物行为受各种内源性和外源性因素的调节，并且天气条件会影响它们的行为。然而，气候变化以及狩猎和捕食压力如何影响欧亚海狸等物种的空间利用和人口统计仍有待测试。我们的研究增加了越来越多的证据，表明动物行为受各种内源性和外源性因素的调节，并且天气条件会影响它们的行为。然而，气候变化以及狩猎和捕食压力如何影响欧亚海狸等物种的空间利用和人口统计仍有待测试。