Since its 2007 discovery in the United States, a fungal disease called white-nose syndrome has killed millions of bats during their winter hibernation. Now, after years of research, scientists are testing ways to help bats survive.

One approach involves using a chemical that coats fungal spores and prevents their growth. Spraying it onto the walls of empty caves in the summer might kill spores by the time bats return for the winter.

Researchers have also found that bats in cooler parts of caves have better survival odds, so another tactic involves cooling some hibernation sites.

Another strategy aims to fatten bats in the summer by planting flowers and grasses that attract a feast of insects. The added energy should help bats survive winter infections.