Resource competition is an important interaction that can structure ecological communities, but is difficult to demonstrate in nature, and rarely demonstrated for large mammals including marsupials. We analysed 10 years of population survey data to investigate resource competition between bare-nosed wombats (Vombatus ursinus) and eastern grey kangaroos (Macropus giganteus) at two sites to assess whether resource competition is occurring. At one site, wombat abundance was reduced by increased mortality from mange disease, whereas at the other site, kangaroo abundance was reduced primarily by culling. We used the modified Lotka–Volterra competition (LVC) models to describe the mechanism of resource competition and fitted those models to the empirical data by maximum likelihood estimation. We found strong negative relationships between the abundance of wombats and kangaroos at each site, and resource competition was also mechanistically supported by the modified LVC models. The estimated competition coefficients indicate that bare-nosed wombats are a slightly superior competitor of eastern grey kangaroos than vice versa, and that intraspecific competition is almost twice as strong as interspecific competition. In addition, this study facilitated the calculation of the transmission rate associated with mange disease at one site (0.011), and the removal rate owing to culling, the introduction of a predator species, and drought at the other site (0.0006). Collectively, this research represents a rare empirical demonstration of resource competition between large mammals and contributes new insight into the ecology of two of Australia’s largest grazing marsupials.

资源竞争是一种重要的相互作用，可以构建生态群落，但在自然界中很难证明，包括有袋动物在内的大型哺乳动物也很少证明。我们分析了 10 年的人口调查数据，以调查裸鼻袋熊 ( Vombatus ursinus ) 和东部灰袋鼠 ( Macropus giganteus ) 之间的资源竞争情况。) 在两个地点评估是否正在发生资源竞争。在一个地点，袋熊的丰度因疥癣病死亡率增加而减少，而在另一地点，袋鼠的丰度主要通过扑杀而减少。我们使用改进的 Lotka-Volterra 竞争 (LVC) 模型来描述资源竞争的机制，并通过最大似然估计将这些模型与经验数据拟合。我们发现每个地点的袋熊和袋鼠丰度之间存在很强的负相关关系，资源竞争也得到了修改后的 LVC 模型的机械支持。估计的竞争系数表明，裸鼻袋熊是东部灰袋鼠的竞争者略胜一筹，反之亦然，种内竞争几乎是种间竞争的两倍。此外，这项研究有助于计算一个地点与疥癣病相关的传播率 (0.011)，以及由于扑杀、引入捕食者物种和另一地点的干旱导致的清除率 (0.0006)。总的来说，这项研究代表了大型哺乳动物之间资源竞争的罕见经验证明，并为澳大利亚两种最大的放牧有袋动物的生态学提供了新的见解。