Effects of disturbance on prairie birds

我研究了栖息地分布和干扰对草原鸟类群落的影响。草原栖息地的丧失是导致草原鸟类数量在过去40年里急剧下降的因素之一。学习如何管理草原和相关的农业将帮助我们保护和恢复草原，使草原鸟类受益。同时，这项研究将有助于我们了解干扰是如何直接和间接地影响草原鸟类。由于干旱草原的牛密度相当低，放牧很少直接破坏鸟巢。尽管如此，在有牛的情况下，筑巢成功率有时会较低。我将确定这是因为放牧对植被的间接影响，还是因为鸟类的无脊椎动物猎物。通过评估各种放牧强度的生态效应，这项研究将帮助我们管理草原上的放牧，使牧场主和野生动物都受益。许多草原被人类活动高度碎片化。鸟类可能会基于许多不同的原因来选择栖息在哪些草原残骸上。例如，它们到达草原的能力、草原内的捕食压力以及无脊椎动物猎物的丰度，都可能在不同的草原上有所不同。所有这些因素都可能受到草原大小、形状和环境的影响。初步调查表明，在小草原上很少发现草原鸣鸟，但原因尚不清楚。我将确定草原大小和周围农田对鸟类、它们的捕食者和猎物使用草原的影响程度。

I study the effects of habitat distribution and disturbance on communities of prairie birds.  Loss of prairie habitats is one of the factors that has resulted in dramatic declines of grassland bird populations over the last four decades.  Learning how to manage prairies and associated agriculture will help us conserve and restore prairies to benefit prairie birds.  At the same time, this research will contribute to our knowledge of how disturbances such as grazing influence prairie birds directly and indirectly.Because cattle densities are quite low in arid prairies, grazing rarely directly destroys nests. Nonetheless, nesting success is sometimes lower in the presence of cattle. I will determine whether this is because of indirect effects of grazing on vegetation or invertebrate prey of birds. By evaluating the ecological effects of a wide range of grazing intensities, this research will help us manage grazing in prairies to benefit both ranchers and wildlife.Many prairies are highly fragmented by human activities. Birds may select which prairie remnants to inhabit based on a number of different reasons. For example, their ability to get to prairies, predation pressure within those prairies, and invertebrate prey abundance, may all vary among prairies. All of these factors may be influenced by prairie size, shape, and surroundings. Preliminary surveys indicate that prairie songbirds are rarely found within small prairies, but the reason for this is unknown. I will determine the extent to which prairie size and surrounding agricultural lands influence prairie use by birds, their predators, and their prey.