Integrating temporal and spatial dimensions of alpine adaptation: Camera-trap insights on bharal (Pseudois nayaur) in Giant Panda National Park
Abstract
Alpine ungulates exemplify climate vulnerability through their spatiotemporal adaptation strategies, yet integrated analyses of these dimensions remain scarce. Here, we investigated how bharal (Pseudois nayaur) in Giant Panda National Park adjust both time-activity budgets and spatial distributions under extreme seasonal conditions. We deployed a network of 50 infrared cameras along altitudinal transects (3,300-4,500 m) during summer and winter. We extracted the Normalized Difference Vegetation Index (NDVI) from satellite imagery for each camera site and calculated the Relative Abundance Index (RAI) to quantify activity intensity and assess its seasonal variation. Our results revealed two key adaptations. (i) Temporal compression: Activity intensity in winter was reduced by 66% compared to summer (RAI: 0.85 ± 0.04 vs. 0.29 ± 0.21; p < 0.01) and exhibited a weaker diurnal-nocturnal contrast (p < 0.05). (ii) Spatial contraction: The bharal’s altitudinal range narrowed by 73% from summer (3,685-4,248 m) to winter (3,859-4,012 m), accompanied by a significant decrease in NDVI (summer: 0.70 ± 0.14 vs. Winter: 0.14 ± 0.06; p < 0.05). These findings reveal a dual-phase adaptation in bharal: expanding activity and range in resource-rich summers and contracting both in winter to conserve energy. By integrating infrared camera data with satellite-derived NDVI, our approach highlights how alpine ungulates respond to seasonal challenges and provides a foundation for predicting climate-driven shifts in high-elevation ecosystems.
Dataset DOI: 10.5061/dryad.hhmgqnktx
Description of the data and file structure
From June 2020 to July 2022, a total of 50 infrared cameras were deployed along an elevation gradient from 3,300 m to 4,500 m in alpine meadow habitats, based on wildlife signs and accessibility. Specifically, 26 cameras were installed at elevations between 3,300 m and 4,000 m, and 24 were placed between 4,000 m and 4,500 m. The specific type of camera used was yianws-L710. The camera parameters were set as follows: photo resolution =1,080 P, video length =10 s, trigger interval =1 min, three photos, and using 24-h time format. The cameras were securely fixed on the tree trunks at height ranging from 0.5 to 1 m along the treeline or on a hand-build rockpile in the meadow. Data collection occurred every 3 or 4 months.
Files and variables
File: data.xlsx
Description: The time, species, and quantity recorded by the infrared camera.
