Reed bed soil stripping as wetland management method: implications for water beetles

Reed bed management is one of the main wetland related issues in Europe and among the diverse approaches developed for that purpose, some restoration methods are considered rather intrusive. There is nonetheless a lack of research investigating how invertebrate communities react to such restoration methods. In this study, we assessed the suitability of reed bed soil strippings, also called bed lowerings, as habitats for aquatic beetles by sampling a total of 101 sites along the southern shore of Lake Neuchâtel, Switzerland. We compared water beetle species richness and taxonomic structure between reed bed soil strippings and other habitats found in the surrounding wetland. Additionally, we evaluated the promotion of new species through strippings and investigated the evolution of water beetle communities along the temporal gradient of reed bed soil strippings. No difference in species composition was found between the sampled habitats, suggesting a well-connected landscape mosaic within the study area. Managed sites did not increase species diversity at the landscape level. We identified a gradual diminution in species richness with age of restored site, as well as a shift in taxonomic assemblages. In conclusion, we advise reed bed soil strippings to be phased temporally and spatially, thus providing managed wetlands open water bodies of different successional stages.