Joseph W. Jones Ecological Research Center, Newton, GA 39870, USA.
Oecologia. 2011 Dec;167(4):1005-16. doi: 10.1007/s00442-011-2053-6. Epub 2011 Jun 26.
Predation and food resources can strongly affect small mammal population dynamics directly by altering vital rates or indirectly by influencing behaviors. Fire may also strongly influence population dynamics of species inhabiting fire-adapted habitats because fire can alter food and cover availability. We used capture-mark-recapture and radio-telemetry studies to experimentally examine how supplemental feeding, mammalian predator exclusion, and prescribed fire affected survival, abundance, and reproduction of hispid cotton rats (Sigmodon hispidus) in southwestern Georgia, USA. Prescribed fire reduced survival, abundance, and rates of transitions to reproductive states. Food supplementation increased survival, transitions to reproductive states, and abundance, but was not sufficient to prevent post-fire declines in any of these parameters. Mammalian predator exclusion did not strongly affect any of the considered parameters. Our results show that fire strongly influenced cotton rat populations in our study site, primarily by reducing cover and increasing predation risk from non-mammalian predators.
捕食和食物资源可以通过改变关键生活史参数直接强烈影响小型哺乳动物的种群动态,或者通过影响行为间接地强烈影响种群动态。火也可能强烈影响适应火的生境的物种的种群动态,因为火可以改变食物和覆盖物的可利用性。我们使用捕获-标记-再捕获和无线电遥测研究来实验性地研究补充食物、哺乳动物捕食者排除和规定的火灾如何影响美国佐治亚州西南部的粗毛棉鼠(Sigmodon hispidus)的存活、丰度和繁殖。规定的火灾降低了存活率、丰度和繁殖状态的转变率。食物补充增加了存活率、繁殖状态的转变率和丰度,但不足以防止在任何这些参数中发生火灾后的下降。哺乳动物捕食者的排除并没有强烈影响到任何被考虑的参数。我们的结果表明,火强烈地影响了我们研究地点的棉鼠种群,主要是通过减少覆盖物和增加来自非哺乳动物捕食者的捕食风险。