McAlpine-Bellis Elizabeth, Utsumi Kaera L, Diamond Kelly M, Klein Janine, Gilbert-Smith Sophia, Garrison Grace E, Eifler Maria A, Eifler Douglas A
Erell Institute Lawrence Kansas USA.
Biodiversity Institute University of Kansas Lawrence Kansas USA.
Ecol Evol. 2023 Aug 10;13(8):e10422. doi: 10.1002/ece3.10422. eCollection 2023 Aug.
Movement is an important characteristic of an animal's ecology, reflecting the perception of and response to environmental conditions. To effectively search for food, movement patterns likely depend on habitat characteristics and the sensory systems used to find prey. We examined movements associated with foraging for two sympatric species of lizards inhabiting the Great Basin Desert of southeastern Oregon. The two species have largely overlapping diets but find prey via different sensory cues, which link to their differing foraging strategies-the long-nosed leopard lizard, , is a visually-oriented predator, while the western whiptail, , relies more heavily on chemosensory cues to find prey. Using detailed focal observations, we characterized the habitat use and movement paths of each species. We placed markers at the location of focal animals every minute for the duration of each 30-min observation. Afterward, we recorded whether each location was in the open or in vegetation, as well as the movement metrics of step length, path length, net displacement, straightness index, and turn angle, and then made statistical comparisons between the two species. The visual forager spent more time in open areas, moved less frequently over shorter distances, and differed in patterns of plant use compared to the chemosensory forager. Path characteristics of step length and turn angle differed between species. The visual predator moved in a way that was consistent with the notion that they require a clear visual path to stalk prey whereas the movement of the chemosensory predator increased their chances of detecting prey by venturing further into vegetation. Sympatric species can partition limited resources through differences in search behavior and habitat use.
运动是动物生态学的一个重要特征，反映了对环境条件的感知和反应。为了有效地寻找食物，运动模式可能取决于栖息地特征和用于寻找猎物的感官系统。我们研究了俄勒冈州东南部大盆地沙漠中两种同域分布蜥蜴的觅食相关运动。这两个物种的食物种类基本重叠，但通过不同的感官线索寻找猎物，这与它们不同的觅食策略有关——长鼻豹纹蜥蜴是视觉导向的捕食者，而西部鞭尾蜥则更依赖化学感应线索来寻找猎物。通过详细的焦点观察，我们描述了每个物种的栖息地利用和运动路径。在每次30分钟的观察期间，我们每分钟在焦点动物的位置放置标记。之后，我们记录每个位置是在开阔地还是在植被中，以及步长、路径长度、净位移、直线度指数和转弯角度等运动指标，然后对这两个物种进行统计比较。与化学感应觅食者相比，视觉觅食者在开阔区域花费的时间更多，移动频率更低且距离更短，并且在植物利用模式上也有所不同。物种之间的步长和转弯角度等路径特征存在差异。视觉捕食者的移动方式符合这样一种观念，即它们需要清晰的视觉路径来跟踪猎物，而化学感应捕食者的移动则通过进一步深入植被增加了检测到猎物的机会。同域分布的物种可以通过搜索行为和栖息地利用的差异来划分有限的资源。
