Eckert James River Bat Cave Preserve

Southwest of the town of Mason near State Highway 29 in Mason County sits the Eckert James River Bat Cave Preserve—one of the largest bat nurseries in the country. About 4 million female bats inhabit the site from May through September. Most of these are pregnant when they arrive. In the Bat Cave, females give birth to a single pup in June or July. The young bats grow rapidly and are able to fly at about five weeks of age. However, they will remain with their mothers until they return to Mexico in October. An hour or two before sunset, hundreds of bats flutter and chirp around the mouth of the cave. Slowly, a stream of bats emerges and flies in a large circle, low to the ground, just outside the cave entrance. These bats gradually spiral upwards and form a dark funnel of flying mammals, reaching several hundred feet into the evening sky. The bats at the top of the spiral break off, forming columns that stream out over the countryside. This seemingly impossible torrent of bats forms a densely packed "bat tornado" for about an hour. Millions of Mexican free-tailed bats can be seen here. Like all bat species, the free-tailed population at the Bat Cave is an integral part of regional ecology. For many years, however, bats were considered menacing creatures to be avoided or destroyed. Thanks to the work of biologists and groups like Bat Conservation International and The Nature Conservancy, this groundless reputation is slowly being corrected.