Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany.
Institute of Organismic and Molecular Evolution (iOME), Johannes Gutenberg University, Gresemundweg 2, 55128, Mainz, Germany.
Parasit Vectors. 2019 Mar 25;12(1):142. doi: 10.1186/s13071-019-3366-2.
The invasive temperate mosquito Aedes japonicus japonicus is a potential vector for various infectious diseases and therefore a target of vector control measures. Even though established in Germany, it is unclear whether the species has already reached its full distribution potential. The possible range of the species, its annual population dynamics, the success of vector control measures and future expansions due to climate change still remain poorly understood. While numerous studies on occurrence have been conducted, they used mainly presence data from relatively few locations. In contrast, we used experimental life history data to model the dynamics of a continuous stage-structured population to infer potential seasonal densities and ask whether stable populations are likely to establish over a period of more than one year. In addition, we used climate change models to infer future ranges. Finally, we evaluated the effectiveness of various stage-specific vector control measures.
Aedes j. japonicus has already established stable populations in the southwest and west of Germany. Our models predict a spread of Ae. j. japonicus beyond the currently observed range, but likely not much further eastwards under current climatic conditions. Climate change models, however, will expand this range substantially and higher annual densities can be expected. Applying vector control measures to oviposition, survival of eggs, larvae or adults showed that application of adulticides for 30 days between late spring and early autumn, while ambient temperatures are above 9 °C, can reduce population density by 75%. Continuous application of larvicide showed similar results in population reduction. Most importantly, we showed that with the consequent application of a mixed strategy, it should be possible to significantly reduce or even extinguish existing populations with reasonable effort.
Our study provides valuable insights into the mechanisms concerning the establishment of stable populations in invasive species. In order to minimise the hazard to public health, we recommend vector control measures to be applied in 'high risk areas' which are predicted to allow establishment of stable populations to establish.
入侵性温带蚊子白纹伊蚊是多种传染病的潜在媒介，因此也是病媒控制措施的目标。尽管它已经在德国建立，但尚不清楚该物种是否已经充分发挥了其分布潜力。该物种的可能范围、其年度种群动态、病媒控制措施的成功以及未来因气候变化而导致的扩张，仍然知之甚少。尽管已经进行了许多关于发生情况的研究，但这些研究主要使用了来自相对较少地点的存在数据。相比之下，我们使用实验生命史数据来模拟连续阶段结构种群的动态，以推断潜在的季节性密度，并询问在一年以上的时间内是否有可能建立稳定的种群。此外，我们还使用气候变化模型来推断未来的范围。最后，我们评估了各种特定阶段的病媒控制措施的有效性。
白纹伊蚊已经在德国西南部和西部建立了稳定的种群。我们的模型预测，在当前气候条件下，白纹伊蚊的分布范围可能会进一步扩大，但不太可能向东扩展太多。然而，气候变化模型将大幅扩大这个范围，并预计每年的密度会更高。对白纹伊蚊的卵、幼虫或成虫进行特定阶段的病媒控制措施应用表明，在晚春至初秋期间，当环境温度高于 9°C 时，应用 30 天的成虫杀虫剂，可以将种群密度降低 75%。持续应用幼虫杀虫剂在种群减少方面也有类似的效果。最重要的是，我们表明，通过应用混合策略，有可能用合理的努力显著降低甚至消灭现有的种群。
我们的研究为入侵物种中稳定种群建立的机制提供了有价值的见解。为了将对公众健康的危害降到最低，我们建议在预计可以建立稳定种群的“高风险地区”应用病媒控制措施。
