Saiga antelopes have suffered catastrophic mass mortality events linked to climate-altered bacterial conditions, alongside ongoing poaching pressure — creating welfare emergencies on a scale affecting entire regional populations.
The 2015 saiga mass mortality event represented one of the most acute wildlife welfare crises of the modern era. Pasteurella bacteria — normally a commensal organism in saiga nasal passages — turned pathogenic under conditions of high temperature and humidity that appeared to trigger explosive bacterial growth. Affected animals developed hemorrhagic septicemia, with death following within hours of symptoms appearing. Eyewitness accounts described mass death scenes of extraordinary scale across the calving grounds. Individual animals died from organ failure and bleeding — a rapid but distressing process. The climate connection means these events are expected to recur more frequently. Poaching for horns continues to reduce populations that might otherwise recover, removing the demographic buffer that allows populations to absorb mortality events.