<scp>Post‐Soviet</scp> fire and grazing regimes govern the abundance of a key ecosystem engineer on the Eurasian steppe, the yellow ground squirrel <i>Spermophilus fulvus</i>

Abstract Aim Grazing intensity and fire patterns across the Eurasian steppes have changed dramatically over past decades due to collapse of Soviet Union in 1991, Kazakhstan is now a global hotspot. The implications these changes for ecosystem functioning are largely unclear. We aimed understand effects grazing frequency on key engineer, yellow ground squirrel Spermophilus fulvus , very large scale. Location Kazakhstan. Methods Ground squirrels were surveyed an area ca. 100,000 ha dry steppe central Kazakhstan, using hierarchical distance sampling at more than 200 random points, stratified by livestock intensity. modelled abundance as function different variables, grouped landscape scale (fire grazing), meso‐scale (soil vegetation structure) burrow (plant traits such palatability, digestibility nutrient content). Results prefer areas high wormwood cover ( Artemisia spp.) plant species richness, which moderately grazed, preferably cattle, with only rare occurrence. High densities also related availability nitrogen‐rich plants nutritional value herbivores. Main Conclusions Yellow seem reach their density optima balancing trade‐offs between optimal foraging short, nutrient‐rich good visibility approaching predators. Post‐Soviet pressure, resulting higher recurrence rates grass encroachment litter accumulation (i.e. fuel wildfire), likely affected burrowing mammals associated biodiversity huge parts semideserts.