Predicting current and future distributions of bird species in South Africa’s arid Northern Cape under climate change scenarios: are biomes being crossed?

Climate change involves rising temperatures and altered precipitation patterns which lead to the contraction, expansion or shift in the ranges of biodiversity. This study employed MaxEnt to predict current and future distributions of three bird species native to South Africa and one invasive species. Future scenarios were modelled for 2050 and 2070 using three pathways: SSP1-2.6, SSP2-4.5 and SSP5-8.5 and four bioclimatic variables. The models showed good performance, with AUC values above 0.7, indicating high predictive accuracy. Comparisons between current ranges and future predictions show species, such as P. purpureus and L. torquatus , moving south-westwards and crossing into new biomes in response to changing climatic conditions. Meanwhile, U. angolensis shows drastic range contraction, with A. tristis showing expansion into arid environments. Across all concentration pathways, for both time periods, all species show expansion into southern arid regions of the Northern Cape. The models suggest that bird species are not only moving to different geographic areas, but are also likely to cross biome boundaries, which may have ecological implications. The study highlights how climate change is a significant driver of changes in bird species distributions and their entry into new biomes. These findings underline the importance of adaptive conservation strategies that consider the dynamic nature of species distributions under climate change.