In the cracks and gaps in the concrete holding up the road deck of Austin’s Ann W. Richards Congress Avenue Bridge (pictured), lives a thriving community of Mexican free-tailed bats. Each summer, the migratory creatures make their home underneath the bridge over Lady Bird Lake and perform captivating aerial displays for onlookers as the sun goes down.

Listed by the Guinness World Records as the largest urban bat colony on the planet, between 750,000 and 1.5 million individuals are thought to reside here from mid-March to as late as mid-October.

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