Influence of the reduction of urban lawn mowing on wild bee diversity (Hymenoptera, Apoidea)

To analyse the effects of reduced green space management in urban areas on the biodiversity of insects, we compared intensely mowed lawns (mowed 12 times per year) with meadows under reduced maintenance (mowed only twice per year) in the city of Tübingen (Baden-Württemberg, Germany). Over the entire field season, 177 wild bee individuals representing 43 species were caught using sweep nets. Areas with reduced maintenance showed significantly higher total species numbers and biodiversity indices. Our research supports the initiative "Bunte Wiese (Colourful Meadow) - Species Diversity in Public Greenspaces" of the University of Tübingen, which is campaigning for the enhancement of species diversity in public urban greenland areas by reorganising intensive mowing into a "twice a year" programme.