Habitat Utilization Preference by Small Mammals Is Associated With Geomorphic and Soil Properties: A Case Study of the Plateau Pika From the Eastern Qinghai-Tibet Plateau.

Amid accelerating climate change, understanding how wildlife adjusts to environmental constraints, particularly via habitat use, is essential. In high-altitude regions with extreme environmental conditions and strong ecological filtering effects, geomorphic and soil characteristics are critical factors influencing habitat utilization preferences. Previous studies of factors affecting wildlife habitat-use preferences have primarily focused on low-altitude areas. However, research remains scarce on the relationship between habitat utilization preferences of small mammals in plateau regions and geomorphic and soil characteristics. In this study, we selected 66 plots from 19 typical distribution areas of pikas in three counties of the Qinghai-Tibetan Plateau to assess the relationship between the pika's habitat-utilization preferences and geomorphic and soil characteristics at a large scale. The results revealed that the factors affecting the habitat use of pikas are potentially similar across regions. The resource selection index (Ei) showed a clear preference for specific geomorphic and soil characteristics. In addition, we found a significant correlation between PC1-PC4 and pika density, and both principal component analysis (PCA) and generalized additive models (GAM) indicated that all geomorphic and soil properties, except soil depth, affect the habitat use of pikas. Overall, pikas preferred flat terrain with a wide field of view ("beach") and sunny, south-facing slopes; including running water sources, with the distance between the preferred habitats to water resources related to the type of water resources. In addition, pikas preferred loam (Ei = 0.258), soil depths > 40 cm (Ei = 0.214) but < 60 cm (Ei = 0.241), soil organic matter between 5% and 15% (Ei = 0.359) and soil moisture between 10% and 20% (Ei = 0.290). Our results highlight that the habitat-utilization preferences of pikas are highly dependent on geomorphic and soil characteristics. Future analyses of factors affecting habitat utilization preferences for small mammals should take geomorphic and soil characteristics into consideration.