Climate warming affects spatio-temporal biodiversity patterns of a highly vulnerable Neotropical avifauna

Global climate change (GCC) is one of the most critical threats to biodiversity. We assessed how it might disrupt the spatio-temporal diversity dimensions of avifauna associated with endangered Neotropical seasonally dry forests (NSDF). We used ecological niche modeling estimating the geographic distributions of 151 highly vulnerable bird species (including swifts, hummingbirds, woodpeckers, and parrots) under current and future climate projections (2050s and 2070s). Then, using traditional metrics of beta-diversity for Sorensen’s index, we assessed how GCC could drive alterations in both alpha and beta taxonomic, phylogenetic, and functional (through birdsong frequencies and acoustic diversity) diversity for bird assemblages across the distribution of NSDF and within current protected areas. Likewise, we estimated the relationship between the expected changes in diversity dimensions with elevation, annual temperature, and precipitation seasonality across the NSDF distribution. Under GCC, we observed a general reduction for spatial taxonomic-richness of birds across the NSDF (−7.24 ± 6.69 spp. [2050s] and − 9.40 ± 7.58 spp. [2070s]), which also implies a general reduction for alpha phylogenetic and functional (except for the acoustic space) diversities by grid-cell. We also observed changes in the potential composition of communities (increasing, on average, the dissimilarity between sites) through space and time. Our results also suggest a biotic heterogenization for NSDF bird assemblages and that protected areas are not exempt from suffering such changes in biodiversity organization. Changes in spatio-temporal diversities were related to high temperatures and low rainfall across lowlands. Our results could inform new land-use planning and beta diversity conservation efforts in NSDF.