Species-specific assessment of climate change vulnerability in Himalayan Pikas and identification of at-risk elevational and latitudinal zones.

Climate change is rapidly transforming high-altitude ecosystems, placing cold-adapted species at risk. We assessed the vulnerability of four Himalayan Pika species (Ochotona macrotis, O. roylei, O. nubrica, and O. sikimaria) by integrating species distribution models with landscape metrics and sensitivity indices. Using verified occurrence records and bioclimatic variables, we projected habitat suitability under moderate (SSP 2-4.5) and extreme (SSP 5-8.5) emission scenarios for 2050 and 2070. We compared eight ecological and anthropogenic indices for two dispersal scenarios to identify species most at risk. Species responses varied, but overall exposure and fragmentation were estimated to decline, with concurrent decline in Protected Area (PA) coverage and increase Human Footprint (HFP). HFP is predicted to increase for most species under a highly restricted dispersal scenario (constrained to the current species' range). Overall, we observed habitat loss, gain and stability within the same elevation bands for three species - O. macrotis and O. nubrica above 4000 m, and for O. sikimaria above 3500 m. Ochotona roylei is predicted to follow upslope range tracking, with habitat loss between 3000 - 4000 m, stable habitat at 4000 - 4500m and gain above 4500 m. Models predicted vulnerability at higher elevations (>4500 m) and latitudes (33-34°N), for O. nubrica, contrasting with the typical trailing-edge loss seen in other pikas. Projections for O. macrotis suggested loss at high latitudes (34-35°N) of its sampled range, indicative of vulnerability driven by internal range fragmentation rather than latitudinal tracking. Based on habitat specialization, sensitivity to climate drivers, and projected range change, our study identified O. roylei as the most vulnerable species. Diverse species-specific habitat and climate drivers challenge the assumption of uniform upward elevational shifts driven solely by climate change. Sustaining the pika guild over the long term will require increased habitat protection and management for habitat connectivity to support range shifts and movement as the Himalaya warms.