Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales.
Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales.
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大鼠尾草种群动态模式与大范围的公共放牧记录相对应。
DOI：
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发表时间：
2017
影响因子：
5
通讯作者：
M. Casazza
中科院分区：
文献类型：
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作者：
A. Monroe;Cameron L. Aldridge;Timothy J. Assal;K. Veblen;D. Pyke;M. Casazza
人类的土地利用，如牲畜放牧，可以对野生动物在共同的生态系统中的相互作用产生深刻而多样的影响，但我们对土地利用影响的理解往往是从短期的，当地的研究，可能不符合更广泛的趋势。在这里，我们使用公共土地记录的特点牲畜放牧整个怀俄明州，美国，我们使用大鼠尾草松鸡（Centrocercus urophasianus）作为模式生物，以评估牲畜管理的反应。在2004-2014年期间，从743列克（繁殖展示点）的雄性鼠尾草松鸡的年度计数，我们模拟了种群趋势，以响应放牧水平（由相对放牧指数表示）和植被生产力梯度的时间，通过归一化植被差异指数（NDVI）测量。我们发现，放牧可以有积极和消极的影响，鼠尾草松鸡种群取决于放牧的时间和水平。鼠尾草，松鸡种群积极响应较高的放牧水平后，高峰植被生产力，但人口下降时，类似的放牧水平发生较早，可能反映了敏感性的冷季草放牧在生长高峰期。我们还发现支持的假设，放牧管理的影响随当地植被生产力。这些结果说明了大规模分析的重要性，揭示模式，在鼠尾草松鸡种群趋势，可能无法推断出在更细的尺度上的研究，并可以告知这些生态系统的可持续放牧管理。
Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) and timing across a gradient in vegetation productivity as measured by the Normalized Vegetation Difference Index (NDVI). We found grazing can have both positive and negative effects on Sage-grouse populations depending on the timing and level of grazing. Sage-grouse populations responded positively to higher grazing levels after peak vegetation productivity, but populations declined when similar grazing levels occurred earlier, likely reflecting the sensitivity of cool-season grasses to grazing during peak growth periods. We also found support for the hypothesis that effects of grazing management vary with local vegetation productivity. These results illustrate the importance of broad-scale analyses by revealing patterns in Sage-grouse population trends that may not be inferred from studies at finer scales, and could inform sustainable grazing management in these ecosystems.