Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tasmania, Australia.
School of Natural Sciences (Biological Sciences), University of Tasmania, Hobart, Tasmania, Australia.
Med Vet Entomol. 2020 Sep;34(3):279-290. doi: 10.1111/mve.12433. Epub 2020 Feb 20.
Saltmarsh breeding mosquitoes are an important source of vectors for arboviral transmission. In southern Australia, the most prominent vector borne disease, Ross River virus (Togaviridae: Alphavirus) (RRV), is transmitted by the saltmarsh mosquito (Diptera: Culicidae) Aedes camptorhynchus (Thomson). However, the factors driving the abundance of this mosquito within and among saltmarshes are poorly understood. To predict the abundance of this mosquito within saltmarshes, the environmental conditions and aquatic invertebrate ecology of three temperate saltmarshes habitats were monitored over two seasons. Up to 44% of first-instar mosquito numbers and 21% of pupal numbers were accounted for by environmental variables. Samphire vegetation cover was a common predictor of first-instar numbers across sites although, between saltmarshes, aquatic factors such as high salinity, temperatures less than 22 °C and water body volume were important predictors. The identified predictors of pupal numbers were more variable and included high tides, waterbody volume and alkalinity. The composition of invertebrate functional feeding groups differed between saltmarshes and showed that an increased diversity led to fewer mosquitoes. It was evident that apparently similar saltmarshes can vary markedly in invertebrate assemblages, water availability and conditions through tidal inundations, rainfall or waterbody permanency. The present study advances insight into predictors of vector mosquito numbers that drive the risk of RRV outbreaks.
盐沼繁殖的蚊子是虫媒病毒传播的重要来源。在澳大利亚南部，最突出的虫媒病是罗斯河病毒（Togaviridae：Alphavirus）（RRV），由盐沼蚊子（双翅目：Culicidae）Aedes camptorhynchus（Thomson）传播。然而，这种蚊子在盐沼内和盐沼之间丰度的驱动因素了解甚少。为了预测盐沼内这种蚊子的丰度，在两个季节监测了三个温带盐沼栖息地的环境条件和水生无脊椎动物生态。多达 44%的一龄蚊子数量和 21%的蛹数量归因于环境变量。尽管在盐沼之间，高盐度、低于 22°C 的温度和水体体积等水生因素是重要的预测因子，但莎草植被覆盖是各站点一龄数量的共同预测因子。蛹数量的确定预测因子更加多变，包括高潮、水体体积和碱度。无脊椎动物功能摄食群的组成在盐沼之间存在差异，表明多样性增加会导致蚊子减少。显然，明显相似的盐沼在无脊椎动物组合、通过潮汐泛滥、降雨或水体永久性获得的水供应和条件方面可能存在明显差异。本研究深入了解了驱动 RRV 爆发风险的病媒蚊子数量的预测因子。
