White-nose syndrome has killed over 90% of some North American bat species, representing one of the most severe wildlife welfare crises in recent decades.
White-nose syndrome represents acute, large-scale wildlife welfare harm through a disease mechanism that causes slow death by starvation during hibernation. Bats disrupted by the fungus burn critical fat reserves that should last the winter, emerging during cold months when no insect prey is available and dying of energy depletion. The scale of mortality - millions of bats - and the mechanism of death - gradual starvation while barely conscious - represent significant welfare harm beyond the ecological consequences. Response efforts including probiotic research and cave management represent welfare-positive interventions, with recovery of resistant populations offering long-term hope.