Bijen en wespen in Nationaal Park De Meinweg

An overview of the bees and wasps (Hymenoptera: Aculeata excluding Formicidae) is given for De Meinweg National Park, a 1700-ha area in the province of Limburg, The Netherlands. As an initiative of several national and regional NGOs, excursions were organised to record at least a thousand species of wildlife in De Meinweg National Park on 9th June 2012. The excursion on bees and wasps visited three locations (Lange Luier, Vlodrop Station and the surroundings of the information centre) and recorded 50 species. Combined with the historical data for De Meinweg, this resulted in 759 records comprising 252 species (117 bee species and 135 wasp species). Vlodrop Station had a high species richness of 107 species, compared to other 1-km squares, but due to varying sampling efforts these findings may be strongly biased. Little overlap was found between species richness of subsequent time periods, but since variations in sampling and species assemblages are confounded, it is difficult to make any statement on real changes in species communities and underlying environmental causes. Standardised surveys on a regular basis could provide better trends in species compositions and a reliable estimate of the total species richness of De Meinweg National Park.