This paper provides a faunistic inventory of Coleoptera species from 13 families, including 40 species collected from the nests of 24 bird species in the North Caucasus. Compared to our previous data, the list of beetle species has been expanded by 2 more species. Around 20 species were identified as accidental visitors to the bird nests, but these are not discussed further in this paper. The remaining species show intricate biocenotic interactions with their host nests. The process of adaptation of species to the nest environment, a form of microbiocenosis, represents a significant evolutionary development that requires further investigation. Geographically, the North Caucasus serves as a refugium for birds, with many species remaining year-round. As a result, the biodiversity of nidicolous Coleoptera is notably higher in this region compared to more northern areas. The data presented here has contributed to a database of beetle species inhabiting bird nests, which will facilitate future studies on the seasonal dynamics of populations and their associations with specific hosts. This research is particularly relevant in light of recent findings on climate change and human impact on natural ecosystems. As bird species decline and the prevalence of synanthropic species increases, it is possible to predict changes in the populations of nidicolous species, some of which have significant sanitary and epidemiological importance.
