thousands of bats in huge caves

animals asia bat bats big biophysics blood brown carrier cave cavedweller caves ceiling cheiropterous common conductor coronavirus coronaviruses covid dangerous disease diseases diseasesampling dungeon dwellers eyes glow glowing hang hibernation huge human infection infections mammals mass mouse nature organism radar sars searchlight sleep sonar southeast speleobios speleology spelunking subterranean suck thousands ultrasound unpleasant vampire vectors vespertilionidae winghanded