Bat populations in the United States face severe threats, including White-nose syndrome (WNS), a disease caused by the fungus Pseudogymnoascus destructans, which can grow on bats while they are hibernating, causing them to burn energy at a time they should be inactive. WNS has been observed in North America since at least 2006 and has spread rapidly across the United States and Canada. The disease has killed millions of bats and continues to spread. Collisions with wind turbines have also caused bat mortalities and contributed to population declines of many species. Even before these multiple mortality events, bats were often killed because of their potential to spread rabies, a zoonotic disease that if left untreated in humans is fatal.