White-nose syndrome has killed billions of North American bats since 2006, representing an ecological catastrophe with profound individual welfare implications.
Bats dying from white-nose syndrome experience a slow death from starvation following repeated arousal from torpor during winter hibernation. Each arousal depletes critical fat reserves, and affected bats emerge in winter when no insect food is available. The cognitive and physiological experience of slow starvation over weeks represents significant individual suffering. The scale of mortality - billions of individuals - represents one of the largest vertebrate welfare disasters in recorded history.