The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in arid ecosystems of Argentina. The Adaptive Flexibility Hypothesis states that populations at the range edge (new populations) will exhibit greater flexibility in use of resources compared to populations located in the range core (older populations). The objective of this work was to compare the rabbit use of spatial and trophic resources in relation to establishment time of their populations. The sampling was carried out for 2 years (2017, 2018) in sites with different establishment times for rabbit populations. Random sampling stratified by type of habitat was applied using 115 fixed strip transects of 1,000 m 2 laid out across the study areas. Fresh rabbit signs were recorded in each transect, and environmental and anthropic variables were measured. Our results show that the individuals from the range edge are more selective in the use of habitat than those from the range core. At the microhabitat level, we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to water. From a trophic perspective, rabbits could show flexible adjustment to novel conditions environments in the range edge. The variability in resource use by the European rabbit confirms its ecological flexibility, pivotal for their advance toward new environments in Argentina.

中文翻译：

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阿根廷巴塔哥尼亚-蒙特入侵前线核心和边缘种群欧洲兔的栖息地和食物偏好

欧洲兔 Oryctolagus cuniculus 是一种外来草食哺乳动物，在阿根廷的干旱生态系统中经历着地理扩张的活跃阶段。适应性灵活性假说指出，与位于范围核心的种群（较老的种群）相比，位于范围边缘的种群（新种群）在资源使用方面将表现出更大的灵活性。这项工作的目的是比较兔子对空间和营养资源的利用与其种群建立时间的关系。采样在不同兔群建立时间的地点进行了两年（2017年、2018年）。使用分布在研究区域内 1,000 m 2 的 115 个固定条带样线进行按栖息地类型分层的随机抽样。在每个样带中记录新鲜兔子的迹象，并测量了环境和人为变量。我们的结果表明，来自山脉边缘的个体比来自山脉核心的个体对栖息地的利用更具选择性。在微栖息地层面，我们观察到兔子使用栖息地的特定组成部分的模式，主要与食物供应和与水的接近程度有关。从营养学的角度来看，兔子可以对范围边缘的新条件环境表现出灵活的适应能力。欧洲兔资源利用的可变性证实了其生态灵活性，这对于它们在阿根廷迈向新环境至关重要。我们观察到兔子使用栖息地的特定组成部分的模式主要与食物供应和与水的接近程度有关。从营养学的角度来看，兔子可以对范围边缘的新条件环境表现出灵活的适应能力。欧洲兔资源利用的可变性证实了其生态灵活性，这对于它们在阿根廷迈向新环境至关重要。我们观察到兔子使用栖息地的特定组成部分的模式主要与食物供应和与水的接近程度有关。从营养学的角度来看，兔子可以对范围边缘的新条件环境表现出灵活的适应能力。欧洲兔资源利用的可变性证实了其生态灵活性，这对于它们在阿根廷迈向新环境至关重要。