This all began in 1980 when a group of engineers designed the reconstruction of the Congress Avenue bridge (recently renamed the Ann Richards bridge...in honor of the former/late governor of Texas). They unwittingly created a design incorporating crevices that became the home to the largest urban bat colony in North America. Although Free-Tail Bats had been living there for years, new bats suddenly began moving in under the bridge by the thousands. It was headline news! Each night at dusk, more than 1.5 million bats emerge from the crevices beneath the bridge to begin their nightly search for food.

After the public became accustomed to this nightly sight, many began to react in fear. Activists within the Austin community started petitioning to have the colony eradicated, until a group now known as Bat Conservation International began a process to educate the community about the bats. Austinites learned that the bats are not only gentle and highly sophisticated creatures, but they eat between 10,000 and 30,000 lbs. of insects (including mosquitoes & agricultural pests) each night! Austin has come to appreciate its bat colony as a revered tourist attraction and erected a bat sculpture in its honor.

The bats migrate from central Mexico each spring. They are Mexican Free-Tail bats. They arrive in mid-March and return to Mexico in early November. Their emergence times from beneath the bridge vary, but as the weather gets drier and hotter, the emergences get earlier.

The best month for viewing is August. This is due to the fact that the newborn bats (called pups) are just learning to forage with their mothers and they come out before sundown. The pups are born in early June. These pink, hairless babies grow to be about 4 inches long with wingspans of up to a foot and able to fly and hunt insects in just 5 weeks.

Every summer night, hundreds of people gather along the Congress Avenue (Ann Richards) bridge to watch as the largest urban bat colony emerges on another nightly flight to forage for food, making our world a better place to live. The bat-watchers have absolutely nothing to fear as long as they don't try to handle the bats.