Seasonal dynamics in terrestrial insect communities after the impact of the Brumadinho tailings dam disaster

Abstract Terrestrial insect communities are key components of ecosystems and sensitive indicators of environmental change. We assessed the effects of the 2019 Brumadinho mining disaster on five insect taxa (ants, bees, butterflies, dung beetles and termites) over 2 years, focusing on their seasonal dynamics across 20 sites representing three habitat categories: fragments adjacent to the mudflow, reference sites and legally protected areas. Despite severe habitat loss, insect species richness, seasonal fluctuations in richness, and temporal β‐diversity did not differ significantly among habitat categories. We suggest that this pattern may reflect a resistance of insect communities to tailings deposition, at least in the short term, coupled with their high dispersal ability, potentially driven by metacommunity connectivity and the buffering effect of the surrounding landscape. Protected areas harboured the greatest number of exclusive species, highlighting their role as biodiversity reservoirs within this disturbed region. We also observed clear general seasonal trends, with higher species richness during the wet season for ants, bees, butterflies and dung beetles, whereas termites showed no significant seasonal variation. Seasonal β‐diversity was predominantly driven by species turnover across the five insect taxa. Our findings reveal that, two years after the disaster, insect communities maintained stable richness and β‐diversity, with seasonal dynamics largely unaffected in forests adjacent to the mudflow. These results sustain the need for long‐term, multitaxa insect monitoring to detect potential delayed or subtle ecological impacts of mining disasters.