Scasta John D, Talley Justin L, Engle David M, Debinski Diane M
Department of Ecosystem Science and Management, University of Wyoming, 1000 E. University Avenue, Laramie, WY 82071 (
Department of Entomology and Plant Pathology, Oklahoma State University, 102 Agricultural Hall, Stillwater, OK 74078 (
Environ Entomol. 2017 Apr 1;46(2):191-200. doi: 10.1093/ee/nvw171.
We assessed local horn fly (Haematobia irritans L.) and face fly (Musca autumnalis De Geer) communities on cattle in 2012 and 2013 relative to vegetation and climate data to understand how parasitism of cattle is influenced by change in climate and vegetation structure. We compared heterogeneity management using spatially and temporally discrete fires (i.e., patch-burning one-third of a pasture annually) to homogeneity management (i.e., burning entire pasture in 2012 then no burning in 2013), with cattle grazing all years in both treatments. Predicted emergence of horn flies and face flies was 24 and 34 d earlier in 2012 associated with earlier spring warming, a significant deviation from the five-year mean. Intraannual horn fly dynamics were explained by concurrent high ambient air temperature the day of observations, but face flies were explained by low ambient air temperatures and dry conditions 3 wk before observations. Importance values of information for the theoretic models including fire treatments ranged from 0.89 to 1, indicating that both horn flies and face flies are sensitive to habitat alterations and fire-driven animal movements. Ordination indicates herds on unburned pastures were dissimilar to herds on pastures burned with patchy fires or pastures burned completely and species-specific fly responses to different vegetation structure metrics. For example, horn flies were correlated with vegetation visual obstruction, and face flies were correlated with woody plant cover. Vegetation structure may be as important as climate in driving the dynamics of fly parasites of cattle.
2012年和2013年，我们评估了牛身上的本地角蝇（Haematobia irritans L.）和厩螫蝇（Musca autumnalis De Geer）群落，并将其与植被和气候数据进行对比，以了解气候和植被结构变化如何影响牛的寄生虫情况。我们将使用空间和时间上离散的火烧（即每年烧三分之一的牧场）的异质性管理与同质性管理（即2012年烧整个牧场，2013年不烧）进行比较，两种处理方式下牛全年都在放牧。2012年，角蝇和厩螫蝇的预计出现时间分别提前了24天和34天，这与春季提前变暖有关，与五年平均值有显著偏差。年内角蝇动态可由观测当天同时出现的高环境气温来解释，而厩螫蝇则可由观测前3周的低环境气温和干燥条件来解释。包括火烧处理在内的理论模型的信息重要性值在0.89至1之间，这表明角蝇和厩螫蝇都对栖息地改变和火烧驱动的动物移动敏感。排序表明，未烧牧场的牛群与进行斑块火烧或完全火烧的牧场的牛群不同，且不同种类的蝇对不同植被结构指标有特定反应。例如，角蝇与植被视觉阻碍相关，厩螫蝇与木本植物覆盖相关。在驱动牛的蝇类寄生虫动态方面，植被结构可能与气候同样重要。
