Caprock Canyons

Bat Etiquette Bats are wild animals and are sensitive to human disturbance. Please remember that this is the bats’ home and you are a visitor here. Mexican Free-tailed Bat Facts h h h Caprock Canyons Trailway h h h S T A T E h P A R K The Bats of h Clarity Tunnel h h h Adults winter in Mexico and possibly further south. h Males and females migrate north separately and roost separately in the summer. h Bracken Cave in Central Texas is home to 20 million Mexican free-tailed bats, the largest known colony in the world. h Mother Mexican free-tailed bats nurse their own pups, not just any pup. h Pups are born in June and begin flying in August/September. h Southern migration occurs primarily in October. 4200 Smith School Road Austin, Texas 78744 www.tpwd.texas.gov PWD BR P4506-079M (11/19) Dispersal of this publication conforms with Texas State Documents Depository Law, and it is available at Texas State Publications Clearinghouse and/or Texas Depository Libraries. TPWD receives funds from the USFWS. TPWD prohibits discrimination on the basis of race, color, religion, national origin, disability, age, and gender, pursuant to state and federal law. To request an accommodation or obtain information in an alternative format, please contact TPWD on a Text Telephone (TTY) at (512) 389-8915 or by Relay Texas at 7-1-1 or (800) 735-2989 or by email at accessibility@tpwd. texas.gov. If you believe you have been discriminated against by TPWD, please contact TPWD, 4200 Smith School Road, Austin, TX 78744, or the U.S. Fish and Wildlife Service, Office for Diversity and Workforce Management, 5275 Leesburg Pike, Falls Church, VA 22041. Q u i t a q u e , T e x a s Denizens of the Dark! Tread softly when you travel through Clarity Tunnel. You are passing beneath the summer residence of a large colony of Mexican free-tailed bats. These bats migrate from Mexico every year to spend the summer at Clarity Tunnel giving birth and raising their young. The tunnel is also home to a fascinating diversity of life. Thousands of invertebrates live their lives in this tunnel in near darkness, scavenging on bats that fall to the tunnel floor. Even though bats have few natural predators, the presence of a large colony attracts many other animals, including birds, mammals and reptiles that come to the tunnel looking for an easy meal. Mexican free-tailed bats have remarkably acute hearing and can pinpoint the location of flying insects in the dark. They do this by echolocation, emitting high frequency calls that are inaudible to humans and then using their large ears and wrinkled skin flaps as sonar receivers. Clarity Tunnel Burlington Northern built this railroad as part of the Fort Worth and Denver South Plains Railway in the early 1920s. Clarity Tunnel was named for a railroad official at the time, Frank E. Clarity. The railroad was completed and began regular freight and passenger service between Lubbock and Estelline in 1928. Clarity Tunnel was included in the National Register of Historic Places in 1977. This rail line was in continual use until 1989 when Burlington Northern closed it. With the help of the Rails-to-Trails Conservancy, Texas Parks and Wildlife acquired the 64 miles of line in 1992. Funding for development of visitor information and interpretation was provided by the Department of Transportation by a federal transportation enhancement grant. Biologists believe that bats began occupying the Tunnel after the last trains traveled through the Tunnel. However, a long-time resident of the immediate area suggests that bats occupied the Tunnel before the railroad stopped running. No matter when the bats began occupying the Tunnel, we know that the bats’ numbers have increased since 1992. Clarity Tunnel’s bat population is estimated from a few hundred thousand to up to a half a million! Beneficial Bats Mexican free-tailed bats play an extremely important role as insect predators and can consume thousands of pounds of insects each night. One insect these bats prey upon is the cotton bollworm moth, which is an agricultural pest. Threats to Mexican Freetailed Bats The number one threat to Mexican free-tailed bats is probably habitat destruction. Other threats include disturbance at roost sites, vandalism and pesticide poisoning. Diseases Bats are known to transmit only two diseases to humans: rabies and histoplasmosis. Like most mammals, few bats contract rabies. Those that do contract it rarely become aggressive. Transmission of rabies usually occurs through a bite. Therefore, bats should never be picked up. Bats that are easily captured are more likely sick and will bite in self-defense. Histoplasmosis is caused by a common ground fungus that lives in soil enriched by bird or bat droppings. Very few individuals may become ill when inhaling large quantities of spore-laden dust.