School of Natural Resources and Environment, University of Florida, 103 Black Hall, Gainesville, Florida, 32611, USA.
Department of Wildlife Ecology and Conservation, University of Florida, 110 Newins-Ziegler Hall, Gainesville, Florida, 32611, USA.
Ecology. 2019 Nov;100(11):e02869. doi: 10.1002/ecy.2869. Epub 2019 Sep 27.
Across landscapes, shifts in species composition often co-occur with shifts in structural or abiotic habitat features, making it difficult to disentangle the role of competitors and environment on assessments of patch quality. Using over two decades of rodent community data from a long-term experiment, we show that a small, ubiquitous granivore (Chaetodipus penicillatus) shifted its use of different experimental treatments with the establishment of a novel competitor, C. baileyi. Shifts in residency, probability of movement between patches, and the arrival of new individuals in patches altered which treatment supported the highest abundances of C. penicillatus. Our results suggest that the establishment of a new species worsened the quality of the originally preferred treatment, likely by impacting resource availability. Paradoxically, the presence of the new species also increased C. penicillatus' use of the less preferred treatment, potentially through shifts in the competitive network on those plots.
在不同的景观中，物种组成的变化通常与结构或非生物栖息地特征的变化同时发生，这使得难以区分竞争和环境在斑块质量评估中的作用。利用长期实验中超过二十年的啮齿动物群落数据，我们表明，一种小型、普遍存在的食虫动物（Chaetodipus penicillatus）随着一种新竞争者 C. baileyi 的建立，改变了其对不同实验处理的利用方式。居留地的变化、在斑块之间移动的可能性以及新个体在斑块中的出现，改变了哪种处理方式支持 C. penicillatus 最高的丰度。我们的结果表明，一个新物种的建立恶化了原本首选处理方式的质量，可能是通过影响资源的可利用性。矛盾的是，新物种的存在也增加了 C. penicillatus 对较不偏好处理方式的利用，这可能是通过那些斑块上的竞争网络的转变。
