Lenticular Tadarida brasiliensis Post CardStandard mailable post card with crisp lenticular images of the free-tailed bat Tadarida brasiiensis commonly know as the Brazilian or Mexican Free-Tailed Bat. Image changes depending on viewing angle. A paragraph with interesting facts about the species appears on the back along with a small distribution range map. These bats are found in the Southwestern U.S. and throughout much of South and Central America. This is the species using the Congress Avenue Bridge in Austin and BCI's protected Bracken Cave as major roosting sites. Bracken Cave is the summer home to 15 million bats, the largest bat colony in the world.