Bats face twin crises in the Northern Hemisphere from white-nose syndrome fungal disease and disturbance of hibernating colonies by cave tourism and exploration.
Bat welfare during hibernation is acutely vulnerable to disturbance. A hibernating bat arouses from torpor only very slowly and at significant energy cost -- each arousal during winter may consume as much energy as the bat can store in two weeks of summer foraging. A bat disturbed multiple times during winter will exhaust its reserves and die from starvation before spring arrives, even if it survives disease. Cave access restrictions during bat hibernation periods are a direct welfare intervention for potentially millions of individual animals. White-nose syndrome adds a disease welfare layer -- bats surviving infection show distress behaviour and emaciation before death.