LTREB: Pulsed Resources and the Dynamics of Rodents, Ticks, and Lyme-disease Risk in Oak Forests

在橡树林中进行的长达七年的观察和实验研究表明，人类接触携带莱姆病蜱虫的风险可以根据橡子产量提前两年预测。秋天大量的橡子刺激了白足鼠的数量增长，导致第二年春夏的鼠密度很高。新孵化的蜱虫幼虫从老鼠身上比从其他宿主身上更容易感染莱姆病细菌。因此，夏季蜱虫幼虫活跃的时候，老鼠的数量越多，以老鼠为食的机会就越大。寄生于大量小鼠体内的幼虫蜱虫在一年后的夏季蜕皮为若虫，导致受感染若虫密度高，因此暴露于莱姆病的风险高，这是在产卵后的两个夏季。该项目将支持在未来五年内继续对橡子产量、啮齿动物种群动态以及蜱病媒介的密度和感染流行率进行核心监测。另外五年的数据将使研究人员能够检验以下假设：(1)橡子产量、夏季小鼠密度和受感染的蜱虫若虫密度之间的显著关系发生在多个寄生周期中；(2)橡子产量与蜱虫密度和感染流行率之间的关系，以及小鼠密度与蜱虫密度和感染流行率之间的关系，最好用线性回归而不是曲线回归来描述。(3)橡子产量与蜱虫密度、感染流行率之间、鼠密度与蜱虫密度、感染流行率之间的显著关系是由于橡子产量极高的杠杆作用造成的；(4)橡子产量不能解释鼠密度、蜱虫密度和感染流行率的年际变化，将由气候的年际变化来解释。核心监测促进了脉冲资源对消费者群落动态影响的相关研究；(2)异质性景观中小鼠扩散的模式和含义；（93）脊椎动物多样性在莱姆病动态中的作用。持续的长期研究将促进群落生态学和流行病学之间的联系。

0075277OstfeldSeven years of observational and experimental studies in oak forests suggest that risk of human exposure to Lyme-disease bearing ticks may be predictable almost two years in advance based on acorn production. High abundance of acorns in the fall stimulates population growth of white-footed mice, resulting in high mouse density the following spring and summer. Newly hatched larval ticks acquire the Lyme disease bacterium more efficiently from mice than from other hosts. Therefore, the greater the abundance of mice in summer, when larval ticks are active, the greater the opportunities to feed on mice. Larval ticks feeding from abundant mice the summer following a mast year molt into nymphs one year later, resulting in high density of infected nymphs, and therefore high risk of exposure to Lyme disease, two summers following mast production. The project will support continued core monitoring of acorn production, population dynamics of rodents, and density and infection prevalence of tick vectors, for the next five years. Five additional years of data will allow investigators to test the hypothesis that (1) significant relationships between acorn production, the summer density of mice, and the density of infected nymphal ticks occur across multiple masting cycles, (2) relationships between acorn production and tick density and infection prevalence, and between mouse density and tick density and infection prevalence, are best described by linear rather than curvilinear regressions, (3) significant relationships between acorn production and tick density and infection prevalence, and between mouse density and tick density and infection prevalence, are caused by the leverage from extremely high acorn production, and (4) interannual variation in mouse density, tick density and infection prevalence not explained by acorn production will be explained by interannual variation in climate. The core monitoring facilitates related research on impacts of pulsed resources on consumer community dynamics, (2) patterns and implications of dispersal by mice in heterogeneous landscapes and 93) the role of vertebrate diversity in Lyme disease dynamics. Continued long-term research will promote linkages between community ecology and epidemiology.