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bioRxiv · 10.64898/2026.01.21.700975

Searching for a New Home or Rare Dispersal? Habitat Suitability and Landscape Connectivity of the Tibetan Brown Bear across the Indian Cold Deserts and the Tibetan Plateau

Abstract

Understanding habitat suitability and landscape connectivity is essential for conserving wide-ranging carnivores in climate-sensitive high-altitude mountain ecosystems. The first occurrence record of the Tibetan brown bear (Ursus arctos pruinosus) from the Changthang region of Ladakh, India, has raised questions about whether this individual represents an isolated dispersal event or reflects functional connectivity with source populations on the Tibetan Plateau. To evaluate potential habitat suitability and transboundary connectivity, we compiled species occurrence records and associated environmental predictors and developed an ensemble species distribution model using biomod2. We then assessed landscape connectivity using circuit theory implemented in Circuitscape to identify potential ecological corridors. Our models indicate that approximately 1,011,818 km{superscript 2} (21.34%) of the combined Ladakh (India) and the Tibetan Plateau landscape is currently suitable for the species, of which only [~]207,000 km{superscript 2} represents highly suitable habitat. Annual precipitation, precipitation of the wettest month, and precipitation of the warmest quarter were the most influential predictors of habitat suitability. Connectivity analysis identified potential corridors linking the eastern Changthang region of Ladakh with suitable habitat on the Tibetan Plateau, suggesting plausible transboundary ecological connectivity. These results indicate that the recent record from Changthang is more likely driven by landscape-scale functional connectivity than by an isolated dispersal event. Although the mapped corridors represent probable connectivity pathways rather than confirmed movement routes, this study provides the first spatially explicit assessment of habitat suitability and potential transboundary connectivity for the Tibetan brown bear across the Ladakh and Tibetan Plateau landscape.

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BibTeXRIS

Kumar, V., Sharief, A., Singh, A. P., Dar, S. A., Joshi, B. D., Thakur, M., Sharma, L. K.. 2026-01-22. Searching for a New Home or Rare Dispersal? Habitat Suitability and Landscape Connectivity of the Tibetan Brown Bear across the Indian Cold Deserts and the Tibetan Plateau. https://doi.org/10.64898/2026.01.21.700975

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