Community-level responses of wild bees to anthropized landscapes

Post-industrial landscapes such as the one found in Northern Europe Belgium are
home to an impoverished community of pollinators, probably as a by-product of ever-increasing
urbanisation and intensive agriculture. Yet, cities within this kind of environments have been
found to host surprisingly diverse assemblages of bees around the globe. As a result, local
policies may want to take advantage of this phenomenon as a lever for conservation, rather than
extending their network of nature reserves. However, the apparent richness found in urban areas
may actually hide ambiguous patterns of diversity, especially when it comes to the distribution
of rare or endangered species.
Our aim was to determine the effect of urbanisation on wild bee richness and evenness
using increasing orders of entropic diversity. Conservation significance was also assessed by
quantifying IUCN threatened species. The relative significance of protected areas in the
conservation of wild bees was examined by comparing their patterns of diversity to the one
found in unprotected areas. Our results suggest that while urbanisation may not have a positive
effect on raw species richness, urban areas harbor a more diverse set of dominant species, albeit
with a conspicuous absence of threatened ones. Conversely, nature reserves may superficially
look as diverse as other types of sites, but they do concentrate rare and declining species.
This research underscores the need for a nuanced approach to biodiversity conservation,
emphasizing the unique contributions of nature reserves in safeguarding vulnerable bee species.