Congress Avenue Bridge bat colony

The Ann W. Richards Congress Avenue Bridge is home to a large colony of Mexican free-tailed bats that emerge nightly from spring through fall; estimates often cite several hundred thousand to over a million bats during peak season. The nightly emergence at dusk is a major wildlife-viewing event that draws residents and tourists to the bridge and adjacent banks of Lady Bird Lake. The bridge colony is the largest urban bat colony in North America and is the subject of ongoing ecological study and public education programs.