The impact of climate change on the spatial distribution of tits and chickadees (Paridae)

Ecological niche models (ENMs), combined with different future emission scenarios, are progressively used to assess the impacts of climate change on global biodiversity. In this study, ENMs, based on current species occurrences and climate data, along with four Shared Socio-economic Pathways representing different greenhouse gas emission scenarios were used to project the future spatial distribution of tits and chickadees (Aves: Paridae). Species-specific traits were subsequently analyzed as potential predictors of range changes. Future latitudinal shifts and area extensions were calculated for 55 parid species and compared to their current distribution. Systematic poleward shifts were found and range restrictions in more than half of the parid species across all future scenarios, with the greatest changes occurring in the worst-case scenario. However, some species showed deviating patterns. Trait analyses revealed that area extension was positively associated with the mean temperature of the warmest quarter and negatively associated with body length, indicating that smaller species in warmer regions may be more likely to expand their ranges under climate change. Latitudinal shift was positively correlated with the current mean latitude, suggesting that more northerly species may be especially sensitive to a changing climate due to limited space for further range shifts. This study provides a comprehensive overview of potential climate change impacts on parid species, highlighting spatial and taxonomic variability in vulnerability, and providing a basis for identifying regions and species that may require targeted conservation efforts.