Predicting the impact of future climate changes and range-shifts of Indian hornbills (family: Bucerotidae)

Climate change influences species distribution and is regarded as a major threat to biodiversity. Hornbills (Family: Bucerotidae) are large tropical birds in Asia and Africa. They are seed dispersers known as forest farmers because they help maintain the ecological community structure by allowing forest regeneration. They are keystone species, and their presence in a forest implies a healthy ecosystem. Range shifts due to climate change is a serious threat because their long-term survival is already imperilled by anthropogenic disturbances. This study models the current and future potential climatic niches of eight of the nine hornbill species present in India. We used GBIF-mediated species presence records along with eight WorldClim V2.1 bioclimatic variables to model the current climatically suitable areas and projected it into the future (mid-century, i.e., 2041-60 and end of the century, i.e., 2081-2100) for different CMIP6 based Shared Socioeconomic Pathway (SSPs) (i.e., SSP126, SSP245, 370 and 585). Range shifts, centroid changes, and the impact of current land use practices for each of the eight species under various climatic conditions were also examined. The Area Under Curve (AUC) values for final models ranged between 0.736 and 0.994. Result indicates that majority of species' climatic niche shift is towards the west, followed by northwest and northern shifts. The species are expected to lose >40% of their suitable present climatic niche under the SSP 585 scenario in 2081-2100. Natural areas were found to be climatically suitable for hornbills throughout the study area, implying the merit of conserving their existing habitats. Our research provides detailed information on how the distribution of Indian Hornbills may change because of future climatic conditions. Detailed spatial and temporal distribution and range shift patterns will aid in a targeted approach for conserving hornbills and their habitat in a changing climate.

Automated summary

Climate change poses a major threat to biodiversity by impacting species distribution. Hornbills, large tropical birds in Asia and Africa, play a crucial role in maintaining ecological community structure through seed dispersal and are considered keystone species. This study models the current and future climatic niches of Indian hornbills, predicting significant shifts and loss of suitable habitats under different climate scenarios.