Changes in habitat suitability and population size of the endangered Przewalski's gazelle

Habitat loss and degradation has become one of the greatest threats to global biodiversity. To protect threatened species, it is essential to explore the spatial-temporal dynamics of its habitat suitability, i.e. the extent of how the habitat quality is suitable for the species. The Przewalski's gazelle Procapra przewalskii is a rare and endangered ungulate endemic to the Qinghai-Tibet Plateau in China. Its historical distribution range covered a large area of the western China, but had shrunk to several fragmented areas around the Qinghai Lake during the 20th century. Along with environment changes and economic development in its current range, the gazelle population size and habitat quality may undergo related changes, which should be studied based on rigorous comparisons. In this study, we conducted field surveys during two periods, from 2009 to 2011 and from 2020 to 2021, to quantify changes in population size of Przewalski's gazelle, and used MaxEnt models to assess the change in its habitat suitability. We found that the overall population size of the species increased from 1544 to 4078, with declines in some subpopulations. The subpopulation changes could be generally related to changes in habitat suitability which exhibited an overall decline but improvement in areas on the northern side of the Qinghai Lake. Among the environmental variables, distance to nearest railways and highways, distance to nearest arable lands, NDVI, and DEM were the key factors affecting habitat suitability of the gazelle. To effectively protect the wild populations of Przewalski's gazelle, we suggest continu-ously monitoring the trends of all subpopulations and critical habitats, constructing ecological corridors, and improving the current conservation systems.