Differently managed reed beds are home to Coleoptera communities differing in diversity, overall biomass and size

Abstract

Reed beds can be managed for commercial or conservation purposes, with effects on its inhabitants. In this paper, we assess the effect of management on the reed bed Coleoptera community by investigating reed beds subject to winter cutting, winter harvest, short-term unmanaged (3 years), and long-term unmanaged (25 years). Using pit fall traps, we collected Coleoptera across a summer season to estimate Coleoptera biomass, abundance, size, richness, diversity, and community composition across the four types of management of reed beds. Cutting and harvest both show to increase Coleoptera biomass compared to unmanaged reed beds, with the highest Coleoptera abundance found in the harvested reed bed. The species richness and diversity, on the other hand, peaked in the long-term unmanaged reed bed. Community composition differed between the different management types, and across time. Species of conservation concern were most abundant in recently managed areas. These results have implications for the conservation of the reed bed Coleoptera community. First, to maintain a high Coleoptera diversity, some areas must be left unmanaged. Secondly, to secure habitats for species of conservation concern as well as boost the Coleoptera biomass, frequent management of other areas is advised. This mosaic management pattern will also create the overall most species rich reed bed, as unique Coleoptera communities were found in each management type.