Multiple movement modes by large herbivores at multiple spatiotemporal scales
Multiple movement modes by large herbivores at multiple spatiotemporal scales
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DOI：
10.1073/pnas.0801737105
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发表时间：
2008-12-09
影响因子：
11.1
通讯作者：
Rosatte, Rick C.
中科院分区：
文献类型：
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作者：
Fryxell, John M.;Hazell, Megan;Rosatte, Rick C.
最近的理论表明，动物应该在规范运动模式之间进行兼性切换，这是内部状态、景观特征、运动能力和导航能力的复杂函数。我们针对时间（分钟到几年）和空间（米到 100 公里）超过 5 个数量级的自由放养麋鹿（Cervus elaphus）测试了这种范式的普遍性。在最粗略的时空尺度上，麋鹿在引入新环境后的 1-3 年内从分散阶段转变为居家活动阶段。在中间时空尺度上，麋鹿继续在运动模式之间交替。在分散阶段，麋鹿在扎营和探索模式之间交替，这可能与动机目标从觅食到社会联系的变化有关。在放牧阶段，麋鹿活动的特点是对首选栖息地类型的吸引力与对先前在放牧范围内活动的记忆之间存在着复杂的相互作用。在最精细的时间和空间尺度上，麋鹿在浏览时使用区域限制的搜索，在不浏览时穿插不太蜿蜒的路径。遇到一片优质食用植物触发了从一种模式到另一种模式的转换，创造了双相运动动态，并因当地资源异质性而得到强化。这些模式表明，多相结构是麋鹿在所有测试的时间和空间尺度上的运动模式的基础。
Recent theory suggests that animals should switch facultatively among canonical movement modes as a complex function of internal state, landscape characteristics, motion capacity, and navigational capacity. We tested the generality of this paradigm for free-ranging elk (Cervus elaphus) over 5 orders of magnitude in time (minutes to years) and space (meters to 100 km). At the coarsest spatiotemporal scale, elk shifted from a dispersive to a home-ranging phase over the course of 1-3 years after introduction into a novel environment. At intermediate spatiotemporal scales, elk continued to alternate between movement modes. During the dispersive phase, elk alternated between encamped and exploratory modes, possibly linked to changes in motivational goals from foraging to social bonding. During the home-ranging phase, elk movements were characterized by a complex interplay between attraction to preferred habitat types and memory of previous movements across the home-range. At the finest temporal and spatial scale, elk used area-restricted search while browsing, interspersed with less sinuous paths when not browsing. Encountering a patch of high-quality food plants triggered the switch from one mode to the next, creating biphasic movement dynamics that were reinforced by local resource heterogeneity. These patterns suggest that multiphasic structure is fundamental to the movement patterns of elk at all temporal and spatial scales tested.