As twilight descends, nocturnal bat species rouse from their daily resting places to feed, creating spectacular clouds as they pour out of caves en masse. But look closer at Jamaican fruit bat colonies as they emerge from sinkhole caves in Cuba, and you may catch a glimpse of a concurrent macabre ritual: As the bats erupt from the cave, a deadly curtain of Cuban boas hangs in their path, aiming to snatch the winged creatures mid-flight.