SGER: Indirect Effects of Biocontrols: Do Gall Fly-induced Increases in Deer Mouse Populations increase the Prevalence of Hantavirus?

[108892 . 92]消费者在食物网中的间接影响在自然生态系统中是重要的，破坏自然食物网的后果有时是灾难性的。然而，我们对间接效应的认识还没有很好地融入到入侵杂草的生物防治理论和实践中。全球引进的外来昆虫超过700种，它们对外来杂草产生直接的负面影响，而对本地物种产生间接的积极影响。然而，初步数据表明，即使是表现良好的生物防治昆虫也可能对本地物种产生深远的间接负面影响。研究表明，20世纪70年代初引入的瘿蝇幼虫，为了控制高度入侵的外来植物，斑点knapweed (Centaurea maculosa和C. diffusa)，可能会产生大量不希望的间接影响，因为它们已经成为鹿鼠丰富的冬季食物来源。鹿鼠是辛诺布雷汉坦病毒的主要传播媒介，人类感染汉坦病毒后死亡率很高。结果表明，捕食瘿蝇幼虫增加了鹿鼠的数量，并导致鹿鼠季节性聚集在高密度的knapweed斑块中，在秋季、冬季和春季，鹿鼠持续大量捕食瘿蝇幼虫。鹿鼠的季节性聚集和种群密度的增加可能会增加汉坦病毒在景观上的流行——特别是在与人类相邻的、蜈蚣草密度很高的地区。将进行实地试验，以验证胆蝇增加汉坦病毒流行率的假设。这项研究的快速实施对于制定管理指南至关重要，以减少生活在西部城市界面和农村环境中的人们感染汉坦病毒的风险。此外，拟议的研究有可能提供广泛的见解，了解被忽视的生物防治的间接影响对自然生态系统的重要性，从而在生物防治和生态学的间接影响领域引入和广泛的新研究机会。

0108892CallawayThe indirect effects of consumers in food webs are known to be important in natural ecological systems, and the consequences of disrupting natural food webs are sometimes disastrous. However, our knowledge of indirect effects has not been well integrated into invasive weed biological control theory and practice. Over 700 species on non-native insects have been introduced worldwide with the expectation that they will have negative direct effects on invasive weeds, resulting in indirect positive effects on native species. However, preliminary data indicate that even well-behaved biocontrol insects may have profound, negative indirect effects on native species. Research indicates that the larvae of gall fly insects introduced in the early 1970's to control the highly invasive exotic plants, spotted knapweed (Centaurea maculosa and C. diffusa), may have substantial undesired indirect effects because they have become an abundant winter food source for deer mice. Deer mice are the primary vectors for the Sin Nombre hantavirus, which results in high mortality when contracted by humans. Results indicate that predation on gall fly larvae increases deer mouse populations and causes deer mice to seasonally aggregate in high-density knapweed patches where the mice persist on large numbers of gall fly larvae during the fall, winter and spring. Seasonal aggregations and increases in population densities of deer mice may increase the prevalence of hantavirus on the landscape - especially in areas adjacent to humans where knapweed reaches high densities. Field experiments will be conducted to test the hypothesis that gall flies increase the prevalence of hantavirus. Rapid execution of this research is critical to developing management guidelines to reduce the risk of hantavirus infection for people living in urban interface and rural settings in the West where spotted knapweed occurs. Moreover, the proposed research has the potential to provide extensive insights into how important the overlooked indirect effects of biocontrols may be to natural ecosystems, thereby introducing and extensive area of new research opportunities in both the fields of biocontrol and indirect effects in ecology.