Bobadilla Sabrina Yasmin, Dacar María A, Jaksic Fabián M, Ojeda Ricardo A, Fernanda Cuevas María
Ecología de Mamíferos de Tierras Secas, IADIZA, CCT-Mendoza CONICET, Av. Ruiz Leal s/n, Parque General San Martín, Mendoza 5500, Mendoza, Argentina.
Laboratorio de Filogeografía, Taxonomía Integrativa y Ecología (LFTIE), IADIZA, CCT-Mendoza CONICET, Av. Ruiz Leal s/n, Parque General San Martín, Mendoza 5500, Mendoza, Argentina.
Curr Zool. 2023 Jul 31;70(3):310-319. doi: 10.1093/cz/zoad033. eCollection 2024 Jun.
The European rabbit is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of Argentina. The Adaptive Flexibility Hypothesis states that populations at the range edge (new populations) will exhibit greater flexibility in the use of resources compared with populations located in the range core (older populations). The objective of this work was to compare the rabbit's use of spatial and trophic resources in relation to the establishment time of their populations. The sampling was carried out for 2 years (2017 and 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 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 and 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.
欧洲野兔是一种外来食草哺乳动物，目前正在阿根廷干旱生态系统中经历一个活跃的地理扩张阶段。适应性灵活性假说指出，与分布范围核心区域的种群（较老的种群）相比，分布范围边缘的种群（新种群）在资源利用方面将表现出更大的灵活性。这项工作的目的是比较野兔在空间和营养资源利用方面与其种群建立时间的关系。在野兔种群建立时间不同的地点进行了为期两年（2017年和2018年）的采样。采用随机抽样，根据栖息地类型分层，在研究区域内设置了115条1000米的固定带状样带。记录每个样带中新鲜的野兔踪迹，并测量环境和人为变量。我们的结果表明，分布范围边缘的个体在栖息地利用上比分布范围核心的个体更具选择性。在微生境水平上，我们观察到野兔在栖息地利用的特定组成部分呈现出一种模式，这主要与食物供应和与水源的距离有关。从营养角度来看，野兔在分布范围边缘可能会对新的条件和环境表现出灵活的适应性。欧洲野兔在资源利用上的变异性证实了其生态灵活性，这对它们在阿根廷向新环境的扩张至关重要。
