bat in a cave during hibernation

animals atmosphere bat bats beauty biophysics blood brown cave common condensation dew dewpoint diapause disgust dormancy down dungeon fear flier flight flittermouse grasping gray hang hibernate hibernation leather leatherwing mat mice moisture morning mouse myotis mystacinus nature night point radar saturation silent silver sleep sleeping soft sonar speleobios suck temperature toy ultrasound unpleasant upside vampire whiskered wing winter