For many centuries, peatlands were drained to make the land accessible for human development. Recent research, however, indicates that in addition to being critical habitats for a wide variety of highly specialized animal and plant species, these unique ecosystems are capable of storing immense amounts of CO2. Today, peatlands are considered key allies in mitigating climate change. Hence, efforts to rewet drained peatlands have gained social and political traction. Nevertheless, little is known about the specific mosquito fauna of peatlands. Many mosquito species can transmit pathogens such as viruses and parasites. Furthermore, international trade and tourism have facilitated the spread of invasive mosquito species. The rewetting of peatlands, combined with the influence of climate change on the spatial and temporal distribution of mosquitoes and mosquito-borne pathogens, may present a health risk to the vicinity of these wetlands.
In order to identify different species compositions and other habitat-specific phenomena and to uncover the underlying mechanisms, we have set up special traps in the Lower Peene Valley, a peatland complex in north-east Germany, and sample mosquito communities biweekly over 24-hour periods. Our sampling sites include rewetted and drained peat soils, drainage pump stations and nearby residential areas. All collected mosquitoes are identified morphologically and, if necessary, genetically. In addition, relevant vector species are analysed for pathogens. Subsequently, we combine our results with climate and weather data, water chemistry parameters and other landscape-specific characteristics to obtain a comprehensive picture of mosquitoes as part of mire ecosystems.
In total, about 75,000 mosquitoes from over 20 species and five genera have been identified so far. While the overall diversity of mosquitoes is similar at all sites, two clearly distinguishable mosquito communities can be identified: one in settlements and one in rewetted sites. The settlement community is dominated by mosquitoes adapted to permanent breeding waters such as rain barrels and garden ponds, while the species that form the wetland community are predominantly adapted to temporary breeding sites such as small puddles or floodplains with dense vegetation. As the vector capacity of each mosquito species differs, it is likely that the different species composition is reflected in the prevalence of pathogens and transmission efficiency. However, it is worth noting that no pathogens have yet been found in the study area. This project will enable us to adequately assess and mitigate the risks associated with peatland rewetting, helping to restore these important habitats while protecting human and animal health.
