10/06/2026
Every evening from spring through fall, close to a million and a half bats pour out from under a bridge in downtown Austin, and people stand on the sidewalk to watch it happen. 🦇
They are Mexican free tailed bats, and the colony under the Congress Avenue Bridge is the largest urban bat colony in North America. Nobody invited them. When the bridge was rebuilt in 1980, the new deck happened to have long narrow crevices underneath that are almost exactly the right width for a bat to wedge into, dark and warm and safe from anything that would eat it. Word got around. Within a few years there were hundreds of thousands of them down there.
The city's first reaction was not delight. There were calls to get rid of them and a general feeling that something had gone badly wrong. 🌆 Then the research came in. The colony eats somewhere between ten and twenty thousand pounds of insects on a summer night, much of it moths that would otherwise be laying eggs in Texas cotton and corn. The bats were running free pest control on an industrial scale. Austin changed its mind completely, and now the nightly emergence is one of the first things people take visitors to see.
If you have stood on that bridge at dusk you know the strange part. 🌙 You do not see them first. You hear a sound like wind moving through dry leaves, and then the column lifts out from under your feet and keeps going for twenty minutes.
Have you watched it, and did it go the way you expected?