Historical and current distribution ranges of the Asiatic black bear (Ursus thibetanus)

Abstract

The current distribution of Asiatic black bear (Ursus thibetanus) is available on the IUCN Red List of Threatened species website; however, nothing is known about the historical extent and occurrence of this species. Therefore, we aimed to understand the historical distribution of the Asiatic black bear, and map and estimate its total size, to compare it with that of species current distribution. In addition, we analyzed a network of protected areas in the past and current ranges of the species. We employed geographic information system (GIS) software to reconstruct and measure the historical range of the Asiatic black bear, comparing past and current ranges to analyze its expected range contraction. The main focus of the study was to enhance our understanding of the species' historical distribution, contributing to better conservation strategies for the present and future perspectives. The utilization of GIS tools facilitates a comprehensive exploration of the factors influencing the species' decline, ultimately aiding in more effective management and conservation efforts. We used published records of black bear’s occurrence in anywhere in history to reconstruct its historical distribution range. Results revealed that the Asiatic black bear was more widely distributed in historical times and its range spanned across approximately 15.86 million km2 while its current range is limited to approximately 7.85 million km2, showing a range contraction of approximately 49.5% (8.02 million km2 reduced). The total protected areas in the historical range of the species were found to be N = 9933, with total size of 0.946 million km2, against N = 6580 (0.667 million km2) that are present in the current range. Approximately 27.5% of the protected areas have lost the Asiatic black bear since historical times.