Walton Zea, Samelius Gustaf, Odden Morten, Willebrand Tomas
Department of Forestry and Wildlife Management, Faculty of Applied Ecology and Agricultural Sciences, Inland Norway University of Applied Sciences, Campus Evenstad, Koppang, Norway.
Snow Leopard Trust, Seattle, Washington, United States of America.
PLoS One. 2017 Apr 6;12(4):e0175291. doi: 10.1371/journal.pone.0175291. eCollection 2017.
Home range size is a fundamental concept for understanding animal dispersion and ecological needs, and it is one of the most commonly reported ecological attributes of free-ranging mammals. Previous studies indicate that red foxes Vulpes vulpes display great variability in home range size. Yet, there has been little consensus regarding the reasons why home range sizes of red foxes vary so extensively. In this study, we examine possible causes of variation in red fox home range sizes using data from 52 GPS collared red foxes from four study areas representing a gradient of landscape productivity and human landscape alteration in Norway and Sweden. Using 90% Local Convex Hull home range estimates, we examined how red fox home range size varied in relation to latitude, elevation, vegetation zone, proportion of agricultural land and human settlement within a home range, and sex and age. We found considerable variation in red fox home range sizes, ranging between 0.95 km2 to 44 km2 (LoCoH 90%) and 2.4 km2 to 358 km2 (MCP 100%). Elevation, proportion of agricultural land and sex accounted for 50% of the variation in home range size found amongst foxes, with elevation having the strongest effect. Red foxes residing in more productive landscapes (those in more southern vegetation zones), had home ranges approximately four times smaller than the home ranges of foxes in the northern boreal vegetation zone. Our results indicate that home range size was influenced by a productivity gradient at both the landscape (latitude) and the local (elevation) scale. The influence of the proportion of agriculture land on home range size of foxes illustrates how human landscape alteration can affect the space use and distribution of red foxes. Further, the variation in home range size found in this study demonstrates the plasticity of red foxes to respond to changing human landscape alteration as well as changes in landscape productivity, which may be contributing to red fox population increases and northern range expansions.
家域大小是理解动物分布和生态需求的一个基本概念，也是自由放养哺乳动物最常被报道的生态属性之一。先前的研究表明，赤狐（Vulpes vulpes）的家域大小存在很大差异。然而，关于赤狐家域大小差异如此之大的原因，目前尚未达成共识。在本研究中，我们利用来自挪威和瑞典四个研究区域的52只佩戴GPS项圈的赤狐数据，研究了赤狐家域大小变化的可能原因，这四个研究区域代表了景观生产力和人类景观改变的梯度。使用90%局部凸壳法估计家域，我们研究了赤狐家域大小如何随纬度、海拔、植被带、家域内农业用地和人类居住区的比例以及性别和年龄而变化。我们发现赤狐家域大小存在相当大的差异，范围在0.95平方公里至44平方公里（90%局部凸壳法）和2.4平方公里至358平方公里（100%最小凸多边形法）之间。海拔、农业用地比例和性别占狐狸家域大小差异的50%，其中海拔的影响最强。生活在生产力更高景观（更南部植被带）的赤狐，其家域大约是北方寒带植被带赤狐家域的四分之一。我们的结果表明，家域大小在景观（纬度）和局部（海拔）尺度上都受到生产力梯度的影响。农业用地比例对狐狸家域大小的影响说明了人类景观改变如何影响赤狐的空间利用和分布。此外，本研究中发现的家域大小差异表明，赤狐具有适应不断变化的人类景观改变以及景观生产力变化的可塑性，这可能有助于赤狐种群数量增加和向北扩展分布范围。
