Saiga antelopes experienced catastrophic mass mortality events killing hundreds of thousands of animals within days, driven by bacterial infections triggered by unusual climate conditions.
The welfare dimension of saiga mass die-off events is staggering in scale. Individual animals dying from Pasteurella septicaemia experience fever, respiratory distress, and systemic collapse over hours to days. The speed of population-level events means that many thousands of animals are simultaneously experiencing suffering across vast steppe landscapes that cannot be reached by any veterinary response. Calves are disproportionately affected, as are pregnant females in late gestation. Survivors must navigate landscapes littered with dead conspecifics, which may have psychological and disease-exposure effects on herd behaviour. The interaction between climate-driven triggers and the physiological vulnerability of an already stressed population demonstrates how welfare and conservation crises are interlinked. Saiga that survive die-offs face depleted social groups and disrupted migration routes.