Tage der Biodiversität 2027

Urban green spaces may facilitate foraging and habitat resources for wild bees. To assess the potential of urban mini forests for wild bee conservation, we investigated five mini forest sites in eastern Austria for wild bee and plant species diversity. We analyzed the effects of surrounding land-use structures and flower richness and abundance on total wild bee species richness and life history traits (LHTs) through generalized linear mixed models. Overall, 97 different wild bee species and 174 different plant species were documented. The bee community was dominated by generalist species (66%), as opposed to specialists (oligolectic; 22%). The wild bee community was composed of mainly solitary species (66%), followed by eusocial species (18%), and parasitic species (12%). The analysis showed that plant richness per se had no direct influence on wild bee species richness or the proportion of oligolectic species, but the number of plants in bloom within the mini forest sites had a strong influence on wild bee species richness, increasing both overall wild bee diversity and the proportion of oligolectic species. Given the ongoing succession of these mini forest sites, however, wild bee diversity is likely to decline over time. Targeted planning and management of such sites are therefore important to support wild bees and promote species associated with open habitats.