Should I Stay or Should I Go? A Habitat-Dependent Dispersal Kernel Improves Prediction of Movement

The analysis of animal movement within different landscapes may increase our understanding of how landscape features affect the perceptual range of animals. Perceptual range is linked to movement probability of an animal via a dispersal kernel, the latter being generally considered as spatially invariant but could be spatially affected. We hypothesize that spatial plasticity of an animal's dispersal kernel could greatly modify its distribution in time and space. After radio tracking the movements of walking insects (Cosmopolites sordidus) in banana plantations, we considered the movements of individuals as states of a Markov chain whose transition probabilities depended on the habitat characteristics of current and target locations. Combining a likelihood procedure and pattern-oriented modelling, we tested the hypothesis that dispersal kernel depended on habitat features. Our results were consistent with the concept that animal dispersal kernel depends on habitat features. Recognizing the plasticity of animal movement probabilities will provide insight into landscape-level ecological processes.

对不同景观中动物运动的分析，有助于深化我们对景观特征如何影响动物感知范围（perceptual range）的理解。感知范围通过扩散核（dispersal kernel）与动物的运动概率相关联，通常认为该扩散核在空间上恒定不变，但亦可能受到空间因素的调控。我们提出假说：动物扩散核的空间可塑性，可极大改变其在时间与空间上的分布格局。本研究通过无线电追踪香蕉种植园内步行昆虫——香蕉假茎象甲（Cosmopolites sordidus）的运动轨迹，将个体运动视为马尔可夫链（Markov chain）的状态，其转移概率取决于当前位点与目标位点的生境特征。结合似然法（likelihood procedure）与模式导向建模（pattern-oriented modelling），我们验证了"扩散核取决于生境特征"这一假说。本研究结果与"动物扩散核依赖生境特征"的理论相符。认识到动物运动概率的可塑性，将为理解景观尺度的生态过程提供新视角。