"This informative title sheds light on a mystery of nature: how little brown bats, nature's insect eaters, are mysteriously dying in their caves during hibernation. Each chapter takes readers into the problems that plague this endangered member of our ecosystem, describing how teams of scientists examined how "white-nose syndrome," caused by a fungus called Pd, is infecting the brown bat population. Scientists have searched different caves and mines in the eastern United States and discovered that Pd affects bats by damaging their wings. Since this discovery, they have been exploring ways to change the conditions so that these small mammals can survive hibernation. The text is written in a clear tone, providing information on the plight of the bats in an accessible style. The book integrates textual and visual information well, and strong back matter allows students to do additional research. An excellent work that will enlighten readers about a growing problem in the natural world."