Parameters of Daurian Pika (Ochotona dauurica) Habitats in Southwestern Transbaikalia

Current climatic and environmental changes necessitate the development of reliable species distribution models to justify management decisions aimed at mitigating their impacts on biodiversity. Such models, in turn, require relevant data on the distribution of species at a local level. The extreme climatic conditions of Daurian pika habitats (hot summers and very cold winters) and its keystone role in ecosystems of North Asian steppes make Daurian pika a suitable model species for analyzing the consequences of climate warming. This paper quantifies predictors determining Daurian pika abundance on a local scale. Eight environmental variables are measured and Daurian pika burrow entrances counted on 236 sampling plots 10 × 10 m² in size. Generalized linear models are used to identify relationships between the chosen environmental predictors and the number of burrow entrances. The best models use the following predictors: projective cover of dense tall vegetation, slope aspect, slope inclination, soil thickness, soil density, and soil stoniness. Daurian pikas are statistically significantly more abundant on plots featuring a thick soil layer covered by dense tall vegetation. The number of burrow entrances is significantly less on north- and east-facing slopes. Burrows are more abundant on gentle slopes and plains and in areas with less dense and stony soils. The models predict the number of burrow entrances on test plots reasonably well. The results demonstrate that the chosen set of abiotic factors accurately predicts the Daurian pika distribution on a local scale. Apparently, the factors that are analyzed include direct ones that potentially affect the Daurian pika distribution in a similar way in any environment. Such direct factors include soil parameters enabling Daurian pikas to make burrows and, probably, vegetation cover. Other factors determine the impact of climate on microclimate and food resources, and their effects vary depending on local environmental conditions.