Large-scale bird co-occurrence stability over time

Recent decades have seen substantial changes in species distributions and community composition, suggesting that environmental change reorganizes ecological communities. Whether such change is accompanied by reorganization of species spatial associations remains largely unknown. We analyzed bird species co-occurrence across four regions (Europe, Czechia, New Zealand, New York State) spanning approximately three decades. Contrary to expectation, co-occurrence patterns were remarkably stable through time. Pairwise changes showed no systematic directional trends and were unrelated to phylogenetic or functional distances and species traits, with only weak habitat-specific trends. Environmental change that shifts co-occurring species coherently while preserving their relative spatial associations might explain this decoupling between local community turnover and species spatial associations. Our results show that substantial biodiversity change can occur without reorganization of species co-occurrences.