A drying climate and habitat availability drive extirpations of a southward advancing ground squirrel.

This article investigates the impacts of climate change and land cover change on the persistence of the Wyoming Ground Squirrel (Urocitellus elegans elegans) across 54 historically occupied sites in the Wyoming Basin and western Colorado. The study found that extirpations at 12 sites were strongly associated with increases in chronic summer atmospheric dryness, measured as minimum summer vapor pressure deficit (VPD), and to a lesser extent, rising mean summer temperatures. Additionally, higher forest cover at the site scale and increased regional rangeland cover were linked to reduced persistence, though these land cover effects were weaker and did not interact with climate variables. These findings suggest that chronic summer climate stressors, rather than acute or winter conditions, are key drivers of local extirpations, highlighting the vulnerability of this diurnal, fossorial species to ongoing climate change and its potential consequences for grassland ecosystem structure and trophic dynamics.