"Effects of disturbance, habitat loss and fragmentation on prairie birds and their ecosystems"

草原鸟类比北美任何其他生态系统的鸟类减少得更多。我研究草原鸣鸟数量下降的原因，以及我们能做些什么。我将理论与实地研究相结合，以更好地了解干扰(包括本地动物的放牧、牛的放牧和火灾)对草原鸣鸟的影响。我还研究了栖息地丧失和碎片化对鸟类的影响。我的研究计划有几个子主题。第一个研究探讨了牲畜放牧的影响。为此，我在萨斯喀彻温省南部的草原国家公园进行了一个放牧实验。我们引入了不同放牧率的牛，以了解放牧强度如何影响鸟类及其生态系统。放牧5年后，我们将把牛从这些牧场上移走，以了解不同放牧强度下草原恢复的速度。 第二个副主题是应用行为生态学来更好地理解为什么大多数鸣禽在更大的草原上有更高的密度。这对马尼托巴省南部高草草原的保护尤为重要，那里剩余的大部分草原都很小，因此草原鸟类避开了它们。一个原因可能是鸣鸟更喜欢在其他鸣鸟附近的草原上定居。为了测试这是否属实，我们将进行一个实验，我们将播放鸟鸣的录音，看看这是否会导致未被占领的草原碎片的重新殖民。 第三个副主题是更好地了解栖息地数量和破碎化对草原鸟类的影响。马尼托巴省西南部有许多濒临灭绝的物种。我们感兴趣的是，草原鸟类的减少是由栖息地丧失直接造成的，例如草原变成农田，还是间接造成的，例如边缘效应。我们正在通过对马尼托巴省西南部的鸟类进行调查来验证这一点，在一系列草地数量和碎片化没有关联的景观中。这将帮助我们确定什么栖息地管理策略最有可能帮助我们保护鸟类。

Grassland birds have declined more than birds from any other ecosystem in North America. I study why grassland songbird populations are declining, and what we can do about it. I integrate theory with field studies to develop a better understanding of effects of disturbance (which includes grazing by native animals, grazing by cattle, and fire) on grassland songbirds. I also study effects of habitat loss and fragmentation on birds. My research program has a number of subthemes. The first explores effects of livestock grazing. To do this, I use a grazing experiment in Grasslands National Park in southern Saskatchewan. We introduced cattle at a range of stocking rates to understand how grazing intensity influences birds and their ecosystems. After 5 years of grazing, we will remove cattle from these pastures, to understand how quickly prairies recover following different grazing intensities. The second subtheme is to apply behavioral ecology to better understand why most songbirds have higher densities in larger prairies. This is particularly important to conservation of tall-grass prairies in southern Manitoba, where most remaining prairies are very small, and thus are avoided by grassland birds. One reason might be that songbirds prefer to settle in prairies near other songbirds. To test if this is true, we will conduct an experiment in which we will play recordings of bird songs to see whether this results in the recolonization of unoccupied prairie fragments. The third subtheme is to better understand effects of habitat amount and fragmentation on grassland birds. South-west Manitoba has many threatened and endangered species. We are interested in whether declines in grassland birds were caused directly by habitat loss, such as conversion of prairies to cropland, or were caused indirectly, for example due to edge effects. We are testing this by surveying birds in south-west Manitoba, in a range of landscapes in which grassland amount and fragmentation are not correlated. This will help us determine what habitat management strategies would be most likely to help us conserve birds.