Monitoring a Nest Aggregation of a Solitary Ground Nesting Bee (Epicharis nigrita Friese) in an Urban Area

Bees are one of the most important ecological (as pollinators of cultivated and wild plant species) and economic (fruits and seeds produced by pollination, and several bee products commercialized and consumed) groups of insects. Most bee species are solitary and ground nesting, and some form nest aggregations that can last for some years. Here, we studied a nest aggregation of Epicharis nigrita Friese from 2013 to 2025 in an urban area. We found that bee populations can vary from one year to the next and may persist for many years despite human interventions in the ground areas used by females to build nests. The aggregation of this species persists for at least 23 years in the area.