Data from: Decreased small mammal and on-host tick abundance in association with invasive red imported fire ants (Solenopsis invicta)

Invasive species may impact pathogen transmission by altering the distributions and interactions among native vertebrate reservoir hosts and arthropod vectors. Here, we examined the direct and indirect effects of the red imported fire ant (Solenopsis invicta) on the native tick, small mammal and pathogen community in southeast Texas. Using a replicated large-scale field manipulation study, we show that small mammals were more abundant on treatment plots where S. invicta populations were experimentally reduced. Our analysis of ticks on small mammal hosts demonstrated a threefold increase in the ticks caught per unit effort on treatment relative to control plots, and elevated tick loads (a 27-fold increase) on one common rodent species. We detected only one known human pathogen (Rickettsia parkeri), present in 1.4% of larvae and 6.7% of nymph on-host Amblyomma maculatum samples but with no significant difference between treatment and control plots. Given that host and vector population dynamics are key drivers of pathogen transmission, the reduced small mammal and tick abundance associated with S. invicta may alter pathogen transmission dynamics over broader spatial scales.外来入侵物种可通过改变本土脊椎动物病原储存宿主与节肢动物媒介的分布及相互作用，进而影响病原传播循环。本研究聚焦得克萨斯州东南部的本土蜱类、小型哺乳动物及病原群落，探究了红色入侵火蚁（Solenopsis invicta）对其产生的直接与间接效应。本研究采用重复大尺度野外操控实验方案，结果表明：在实验性降低红色入侵火蚁种群数量的处理组样地中，小型哺乳动物的丰度更高。通过对小型哺乳动物宿主体表蜱类的分析，我们发现相较于对照组样地，处理组样地内单位捕获努力量下捕获的蜱虫数量提升了三倍；且在一种常见啮齿动物宿主身上，蜱虫寄生负荷增长了27倍。本研究仅检出1种已知人类病原——帕氏立克次体（Rickettsia parkeri），其在宿主体表美洲花蜱（Amblyomma maculatum）的幼虫样本中检出率为1.4%，若虫样本中检出率为6.7%，但处理组与对照组样地间未发现显著差异。鉴于宿主与媒介种群动态是病原传播的关键驱动因子，与红色入侵火蚁相关的小型哺乳动物及蜱类丰度下降，或可在更大空间尺度上改变病原传播动态。