University of Grenoble Alpes, University of Savoie Mont Blanc, CNRS, LECA, Grenoble, France.
Office Français de la Biodiversité, Unité Ongulés Sauvages, Juvignac, France.
J Anim Ecol. 2022 Feb;91(2):443-457. doi: 10.1111/1365-2656.13633. Epub 2021 Dec 9.
Understanding the consequences of global change for animal movement is a major issue for conservation and management. In particular, habitat fragmentation generates increased densities of linear landscape features that can impede movements. While the influence of these features on animal movements has been intensively investigated, they may also play a key role at broader spatial scales (e.g. the home range scale) as resources, cover from predators/humans, corridors/barriers or landmarks. How space use respond to varying densities of linear features has been mostly overlooked in large herbivores, in contrast to studies done on predators. Focusing on large herbivores should provide additional insights to understand how animals solve the trade-off between energy acquisition and mortality risk. Here, we investigated the role of anthropogenic (roads and tracks) and natural (ridges, valley bottoms and forest edges) linear features on home range features in five large herbivores. We analysed an extensive GPS monitoring database of 710 individuals across nine populations, ranging from mountain areas mostly divided by natural features to lowlands that were highly fragmented by anthropogenic features. Nearly all of the linear features studied were found at the home range periphery, suggesting that large herbivores primarily use them as landmarks to delimit their home range. In contrast, for mountain species, ridges often occurred in the core range, probably related to their functional role in terms of resources and refuge. When the density of linear features was high, they no longer occurred predominantly at the home range periphery, but instead were found across much of the home range. We suggest that, in highly fragmented landscapes, large herbivores are constrained by the costs of memorising the spatial location of key features, and by the requirement for a minimum area to satisfy their vital needs. These patterns were mostly consistent in both males and females and across species, suggesting that linear features have a preponderant influence on how large herbivores perceive and use the landscape.
了解全球变化对动物运动的影响是保护和管理的一个主要问题。特别是，生境破碎化产生了更多的线性景观特征，这些特征会阻碍动物的运动。虽然这些特征对动物运动的影响已经被深入研究，但它们在更广泛的空间尺度上（例如，栖息地范围尺度）也可能起着关键作用，如资源、来自捕食者/人类的掩护、走廊/障碍物或地标。动物如何对不同密度的线性特征做出空间利用的响应，在大型食草动物中大多被忽视，而与对捕食者的研究相比。关注大型食草动物应该提供额外的见解，以了解动物如何在获取能量和死亡风险之间做出权衡。在这里，我们研究了人为（道路和轨道）和自然（山脊、山谷底部和森林边缘）线性特征对五种大型食草动物的栖息地特征的作用。我们分析了一个广泛的 GPS 监测数据库，该数据库涵盖了 9 个种群的 710 个个体，这些种群的范围从主要由自然特征分隔的山区到高度被人为特征分割的低地。几乎所有研究的线性特征都出现在栖息地的周边，这表明大型食草动物主要将它们用作界定栖息地的地标。相比之下，对于山地物种，山脊通常出现在核心区域，这可能与它们在资源和避难所方面的功能作用有关。当线性特征的密度较高时，它们不再主要出现在栖息地的周边，而是分布在整个栖息地范围内。我们认为，在高度破碎的景观中，大型食草动物受到记忆关键特征空间位置的成本的限制，以及满足其基本需求所需的最小面积的限制。这些模式在雄性和雌性以及不同物种中基本一致，表明线性特征对大型食草动物如何感知和利用景观具有主导影响。
