Van Moorter Bram, Rolandsen Christer M, Basille Mathieu, Gaillard Jean-Michel
Norwegian Institute for Nature Research, Trondheim, Norway.
Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, FL, USA.
J Anim Ecol. 2016 Jan;85(1):21-31. doi: 10.1111/1365-2656.12394. Epub 2015 Jul 30.
Animal space use has been studied by focusing either on geographic (e.g. home ranges, species' distribution) or on environmental (e.g. habitat use and selection) space. However, all patterns of space use emerge from individual movements, which are the primary means by which animals change their environment. Individuals increase their use of a given area by adjusting two key movement components: the duration of their visit and/or the frequency of revisits. Thus, in spatially heterogeneous environments, animals exploit known, high-quality resource areas by increasing their residence time (RT) in and/or decreasing their time to return (TtoR) to these areas. We expected that spatial variation in these two movement properties should lead to observed patterns of space use in both geographic and environmental spaces. We derived a set of nine predictions linking spatial distribution of movement properties to emerging space-use patterns. We predicted that, at a given scale, high variation in RT and TtoR among habitats leads to strong habitat selection and that long RT and short TtoR result in a small home range size. We tested these predictions using moose (Alces alces) GPS tracking data. We first modelled the relationship between landscape characteristics and movement properties. Then, we investigated how the spatial distribution of predicted movement properties (i.e. spatial autocorrelation, mean, and variance of RT and TtoR) influences home range size and hierarchical habitat selection. In landscapes with high spatial autocorrelation of RT and TtoR, a high variation in both RT and TtoR occurred in home ranges. As expected, home range location was highly selective in such landscapes (i.e. second-order habitat selection); RT was higher and TtoR lower within the selected home range than outside, and moose home ranges were small. Within home ranges, a higher variation in both RT and TtoR was associated with higher selectivity among habitat types (i.e. third-order habitat selection). Our findings show how patterns of geographic and environmental space use correspond to the two sides of a coin, linked by movement responses of individuals to environmental heterogeneity. By demonstrating the potential to assess the consequences of altering RT or TtoR (e.g. through human disturbance or climatic changes) on home range size and habitat selection, our work sets the basis for new theoretical and methodological advances in movement ecology.
动物空间利用的研究主要集中在地理空间（如活动范围、物种分布）或环境空间（如栖息地利用与选择）。然而，所有空间利用模式都源于个体的移动，而个体移动是动物改变环境的主要方式。个体通过调整两个关键移动要素来增加对特定区域的利用：停留时间和/或回访频率。因此，在空间异质性环境中，动物通过增加在优质资源区域的停留时间（RT）和/或缩短返回这些区域的时间（TtoR）来利用已知的优质资源区域。我们预期这两种移动特性的空间变化会导致在地理空间和环境空间中观察到的空间利用模式。我们得出了一组九个预测，将移动特性的空间分布与新兴的空间利用模式联系起来。我们预测，在给定尺度下，不同栖息地之间RT和TtoR的高变化会导致强烈的栖息地选择，而长RT和短TtoR会导致较小的活动范围。我们使用驼鹿（Alces alces）的GPS跟踪数据检验了这些预测。我们首先建立了景观特征与移动特性之间的关系模型。然后，我们研究了预测的移动特性的空间分布（即RT和TtoR的空间自相关性、均值和方差）如何影响活动范围大小和分层栖息地选择。在RT和TtoR具有高空间自相关性的景观中，活动范围内RT和TtoR都有很大变化。正如预期的那样，在这样的景观中活动范围位置具有高度选择性（即二阶栖息地选择）；与活动范围外相比，所选活动范围内的RT更高，TtoR更低，驼鹿的活动范围较小。在活动范围内，RT和TtoR的更高变化与栖息地类型之间更高的选择性相关（即三阶栖息地选择）。我们的研究结果表明，地理空间和环境空间利用模式如何对应于同一枚硬币的两面，通过个体对环境异质性的移动反应联系在一起。通过证明评估改变RT或TtoR（例如通过人为干扰或气候变化）对活动范围大小和栖息地选择的影响的潜力，我们的工作为运动生态学的新理论和方法进展奠定了基础。
