Department of Wildland Resources and Ecology Center, Utah State University , Logan, UT, USA.
Nevada Department of Wildlife , Reno, NV, USA.
Philos Trans R Soc Lond B Biol Sci. 2024 Oct 21;379(1912):20220533. doi: 10.1098/rstb.2022.0533. Epub 2024 Sep 4.
The spatial availability of social resources is speculated to structure animal movement decisions, but the effects of social resources on animal movements are difficult to identify because social resources are rarely measured. Here, we assessed whether varying availability of a key social resource-access to receptive mates-produces predictable changes in movement decisions among bighorn sheep in Nevada, the United States. We compared the probability that males made long-distance 'foray' movements, a critical driver of connectivity, across three ecoregions with varying temporal duration of a socially mediated factor, breeding season. We used a hidden Markov model to identify foray events and then quantified the effects of social covariates on the probability of foray using a discrete choice model. We found that males engaged in forays at higher rates when the breeding season was short, suggesting that males were most responsive to the social resource when its existence was short lived. During the breeding season, males altered their response to social covariates, relative to the non-breeding season, though patterns varied, and age was associated with increased foray probability. Our results suggest that animals respond to the temporal availability of social resources when making the long-distance movements that drive connectivity. This article is part of the theme issue 'The spatial-social interface: a theoretical and empirical integration'.
据推测，社会资源的空间可用性会影响动物的运动决策，但由于社会资源很少被测量，因此很难确定社会资源对动物运动的影响。在这里，我们评估了在美国内华达州，关键社会资源（即接受配偶的机会）的可利用性变化是否会对绵羊的运动决策产生可预测的变化，因为这些运动决策是连通性的关键驱动因素。我们比较了雄性在三个生态区进行长途“突袭”运动（一种关键的连通性驱动因素）的概率，这三个生态区的社会中介因素（繁殖季节）的持续时间不同。我们使用隐马尔可夫模型来识别突袭事件，然后使用离散选择模型来量化社会协变量对突袭概率的影响。我们发现，当繁殖季节较短时，雄性进行突袭的频率更高，这表明当社会资源存在的时间较短时，雄性对其的反应最敏感。在繁殖季节，雄性相对于非繁殖季节对社会协变量的反应发生了变化，尽管模式有所不同，并且年龄与增加突袭的可能性有关。我们的结果表明，动物在进行远距离运动时会对社会资源的时间可用性做出反应，这些运动驱动着连通性。本文是主题为“空间-社会界面：理论和经验整合”的特刊的一部分。
