Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.
J Anim Ecol. 2020 Mar;89(3):772-783. doi: 10.1111/1365-2656.13129. Epub 2019 Dec 17.
Territoriality and stable home ranges are a common space-use pattern among animals. These ranges provide its inhabitants with important resources and thus favourable territories are associated with an increased fitness. While the role of territory quality and changes of territory ownership have often been investigated, the changes of territorial boundaries have been less studied. Here, we investigated space-use changes in a social mammal species, applying a novel analytical approach, calculating long-term dissimilarity in space use using distancematrices based on periodic utilization distributions. This approach makes it possible to identify different space-use patterns, which cannot be distinguished by only considering changes between consecutive time periods. We analysed meerkat (Suricata suricatta) movements of a total of 24 different groups over a 16-year period, resulting in 134 group years. We then correlated the identified home-range changes to life-history events and possible environmental drivers. Groups had stable territories for several years before they abandoned their home range mostly to move quickly to new areas where they again remained for several years. Of 26 identified sudden shifts, 22 occurred in the summer months and often involved distances larger than the original home-range size. Home-range movements that were close together in time were often also spatially clustered and moved in a similar direction. These shifts were often preceded by more frequent interactions between groups, but did not seem to be a product of direct displacements by other groups. The normalized difference vegetation index as a measure of food production and social factors such as dominance changes did not correlate to changes. Against our expectation space-use changes were not accumulations of small changes, but more often involved long-distance moves into unknown ranges. This means that the groups enter areas where they cannot profit from local knowledge. The methods used identify episodes of long stability alternated by sudden changes in meerkats and in general provides insight into long-term space use. Our methods can be used to analyse long-term space use, either within or across species.
领域性和稳定的家域是动物常见的空间利用模式。这些范围为其居民提供了重要的资源，因此有利的领地与更高的适应性相关。虽然领地质量和领地所有权的变化经常被研究，但领地边界的变化研究较少。在这里，我们通过一种新的分析方法研究了一种社会哺乳动物的空间使用变化，该方法通过基于周期性利用分布的距离矩阵计算长期空间使用的不相似性。这种方法使得识别不同的空间使用模式成为可能，仅考虑连续时间段之间的变化是无法区分这些模式的。我们分析了总共 24 个不同群体的 16 年期间的猫鼬（Suricata suricatta）运动，得出了 134 个群体年。然后，我们将识别出的家域变化与生活史事件和可能的环境驱动因素相关联。群体在放弃其家域之前，通常会稳定地占据其领地数年，主要是快速迁移到新的区域，然后在这些新的区域中又会稳定地占据数年。在 26 个识别出的突然转变中，有 22 个发生在夏季，通常涉及的距离大于原始家域的大小。时间上接近的家域运动通常在空间上也聚集在一起，并朝相似的方向移动。这些转变通常发生在群体之间的互动更加频繁之前，但似乎不是其他群体直接排挤的结果。归一化差异植被指数（NDVI）作为食物产量的衡量标准，以及社会因素（如支配地位的变化）与变化无关。与我们的预期相反，空间使用变化不是小变化的积累，而是更多地涉及长途迁徙到未知的范围。这意味着这些群体进入了它们无法从本地知识中获益的区域。所使用的方法确定了猫鼬的长时间稳定期与突然变化期的交替，总体上为长期空间使用提供了深入的了解。我们的方法可以用于分析物种内或跨物种的长期空间使用。
