National Geographic

The toothy, hungry bats have long, nearlytransparent bunny-like ears and wrinkled,wolfy faces with a lance-shaped nose leaf—an appendage that bats use for echolocation—on top of their snouts.These mysterious bats just outside the Calak-mul Biosphere Reserve, in the Yucatán Peninsula,don’t roost in the thousands like some other spe-cies, said Rodrigo Medellín, the country’s leadingexpert on the flying mammals and a professor atthe National Autonomous University in MexicoCity. “They’re always in these small groups—they’re very protective of one another.”Medellín swung his butterfly net at one ofthe six bats, catching it. He held the animal ina leather-gloved hand so we could examine thebat’s thick, woolly fur, which made it look sweetand cuddly, and its protruding snout and sharpteeth, which made it look anything but. Thiswas a female, and she chattered her jaws at us,protesting. Medellín gently stretched out oneof her wings and pointed to the bat’s thumb,which curved out from the edge. It was armedwith a pronounced claw, shaped like a saber andjust as sharp.“That’s what they use to lock their prey,” he``````said. From the size of this weapon, you knowthese hunters of the night aren’t slashingmosquitoes—they’re after rodents, songbirds,even other bats.Carnivorous bats, known collectively as falsevampire bats because they don’t drink the bloodof animals, as true vampire bats do, are foundthroughout the tropics, although in low num-bers: Less than one percent of all bat species eatother vertebrates.Two species are found from southern Mexicoto Bolivia and Brazil, with one even extendingfarther south into parts of Paraguay and Argen-tina: the woolly false vampire bat (the ones inthe Maya temple) and the spectral bat, alsocalled Linnaeus’s false vampire bat. The latterare the largest of the New World bats, somewith wings spanning up to three feet. Threatsto their rain forest habitats are putting pressureon Mexico’s bats—and adding urgency to efortsto understand their ways.Little is known about woolly false vampirebats, so Medellín caught all six and broughtThey hang from the cold, stoneceiling of an ancient Mayatemple like a bunch of fuzzy grayfruits, staring down at us witheyes that shine golden in the redglow of our headlamps.The nonprofit National Geographic Society, workingto conserve Earth’s resources, helped fund this article.78 NATIONAL GEOGRAPHIC