Biotic interactions under risk: climate change drives spatial mismatch between a critically endangered tree and its seed dispersers and predators

Climate change affects biodiversity through shifts in species distribution range and composition of biological communities. However, the consequences of these changes for the spatial association between species and ecosystem services are poorly known. Here, we assessed the effects of climate change on the distribution mismatch between araucaria, a critically endangered keystone species in the Atlantic Forest hotspot, and its community of seed dispersers and predators. Ecological niche models were employed to compare the distribution of the plant to those predicted for its dispersers and predators under two different climate change scenarios. Our projections revealed a pronounced contraction in the habitats climatically suitable for araucaria of up to 76% depending on the year and climate change scenario. In addition, we found a species-specific response to climate change that resulted in different levels of spatial mismatch between araucaria and its community of dispersers and predators. Significant changes in the spatial mismatch compared to current conditions were predicted for 70% of the seed dispersers and 83% of the seed predators. Interestingly, our projections showed a distinct pattern in the changes in the richness of dispersers and predators within the distribution range of araucaria, suggesting a risk of unbalance in seed dispersal and predation in some regions. The climate-driven decoupling of geographical distributions forecasted in some regions may contribute to the disruption of biotic interactions, with potential consequences for conserving araucaria and the fauna that depends on its seeds as a food source. To minimize these risks, initiatives involving not only the conservation of forest remnants but also the restoration of degraded areas using araucaria are crucial to safeguard this species and its biotic interactions. Also, the indirect effect on the biotic interactions should be considered when assessing the impacts of climate change on biodiversity, especially regarding the conservation of threatened species. The dataset consists of two folders containing the species occurrence records and the study area used to sample the background points used in the modeling process.