The City that Is Home to Millions of Bats

David Miller

When bats began migrating to Austin, Texas in the early 1980s, locals were afraid that the bats would be a rabies spreading menace. But in the three decades that they’ve been coming to Austin they’ve become a part of the city’s identity and an unofficial mascot.

Every summer evening at sunset, boats fill the water of Lady Bird Lake and people line the railings of the Congress Avenue Bridge to watch the bats fly from underneath the bridge to feed on bugs for the evening.

At the peak of summer there are more than 1.5 million bats that leave their home under the bridge all at once, filling the nights sky with a dark cloud of bats.

Around 750,000 mostly pregnant female bats migrate from Mexico every spring and colonize under the bridge to give birth in the summer. Once the bats have their pups, the number grows to more than 1.5 million.

The city of Austin never intended to become the summer home of the Mexican free-tailed bats. Without realizing it, a chance expansion to the Congress Avenue Bridge and the addition of expansion joints created the perfect home for the bats.

There was initially a lot of fear that the bats were going to be a problem and spread disease, but over time that attitude changed.

“Once the town realized it wasn’t going to be murdered by bats and that the bats can stay and live in peace with people, then they started thinking that maybe we should make this a tourist attraction,” said Bat Conservation International’s Dianne Odegard.