Abstract
Invasive mosquito species and the pathogens they transmit represent a serious health risk to both humans and animals. Thus, predictions on their potential geographic distribution are urgently needed. In the case of a recently invaded region, only a small number of occurrence data is typically available for analysis, and absence data are not reliable. To overcome this problem, we have tested whether it is possible to determine the climatic ecological niche of an invasive mosquito species by using both the occurrence data of other, native species and machine learning. The approach is based on a support vector machine and in this scenario applied to the Asian bush mosquito (Aedes japonicus japonicus) in Germany. Presence data for this species (recorded in the Germany since 2008) as well as for three native mosquito species were used to model the potential distribution of the invasive species. We trained the model with data collected from 2011 to 2014 and compared our predicted occurrence probabilities for 2015 with observations found in the field throughout 2015 to evaluate our approach. The prediction map showed a high degree of concordance with the field data. We applied the model to medium climate conditions at an early stage of the invasion (2011–2015), and developed an explanation for declining population densities in an area in northern Germany. In addition to the already known distribution areas, our model also indicates a possible spread to Saarland, southwestern Rhineland-Palatinate and in 2015 to southern Bavaria, where the species is now being increasingly detected. However, there is also evidence that the possible distribution area under the mean climate conditions was underestimated.
Highlights
Due to globalisation, facilitating long-distance traffic, mass tourism and worldwide trade, increasing numbers of invasive mosquitoes have recently arrived and subsequently established themselves in Germany and mainland Europe (Medlock et al 2015)
The concentration of predicted suitable regions for Ae. j. japonicus in western Germany (Baden-Wuerttemberg, Rhineland-Palatinate, Hesse, North Rhine-Westphalia) is not surprising, as we had a high amount of training data from these regions
Our model approach appears to be suitable for predicting the distribution area of the Asian bush mosquito Ae. j. japonicus in newly invaded areas
Summary
Due to globalisation, facilitating long-distance traffic, mass tourism and worldwide trade, increasing numbers of invasive mosquitoes have recently arrived and subsequently established themselves in Germany and mainland Europe (Medlock et al 2015). As they include potential vectors of a wide range of human and animal pathogens (Schaffner et al 2013; Becker et al 2014), they have become a major research issue. The first step should be to identify the climatic niche within the invaded area This is challenging because the spread of invasive
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have