Bracken Cave, Texas (IMAGE) Rothamsted Research Caption This photo shows dusk at Bracken Cave, on the outskirts of San Antonio, site of the world's largest colony of Brazilian free-tailed bats and where millions roost. Credit Phillip Stepanian/Rothamsted Research Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.