Life Science and Medical News from Around the Globe
First Direct Evidence That Migratory Bat Hibernates
Perched among the branches and needles of California's redwood forests are nestled wayfaring hoary bats (Lasiurus cinereus). A migratory species capable of traveling hundreds of miles, hoary bats may wander throughout western North America before settling into California's north coast...to sleep. While it is not unusual for some species of bat to migrate or other species to hibernate, it is unusual to find a species of bat that does both. Hoary bats are one of North America's largest bats at 5 inches in length and also one of the continent's most distinguished with its frosted fur from which it takes its name. Researchers with the U.S. Forest Service's Pacific Southwest Research Station have documented the first recorded evidence of hoary bats going into a state of torpor, or hibernation. Published online on October 4, 2016 in Scientific Reports and just in time for National Bat Week, October 24-31, "First Direct Evidence of Long-Distance Seasonal Movements and Hibernation in a Migratory Bat" reports newly discovered behaviors in hoary bats. "It's commonly assumed that species that migrate do so to reach areas that allow them to continue feeding and remain somewhat active throughout the winter," said lead author Ted Weller, Ph.D., an ecologist with the Forest Service. "But our findings surprised even our own research team by showing that hoary bats spend much of the winter in hibernation." In September 2014, Dr. Weller and his colleagues tagged several bats within Humboldt Redwoods State Park with GPS tracking devices and another group of bats with a device that monitored light levels, body temperatures, and activity, which allowed them to understand how bats responded to varying weather conditions.