Every spring Mexican free-tail bats set up housekeeping under the Congress Street bridge.
It's the largest "urban" community in North America and approaches 1.5 million by midsummer after the babies are born. Here the sun is just setting. (Notice the construction cranes in downtown background).
People beginning to congregate on the bridge in anticipation of the show. The bats "drop" out of their summer homes, then fly along the bridge to the south shore of Lady Bird Lake before heading out to the East for a night of hunting insects.
Sun setting, that's the 1st Street bridge in bottom of picture.
Lamppost at south end of bridge and ribbon of bats flying over tree tops.
(July almost full moon).
More ribbons of bats flying east. These continue on and off for a couple hours. Under the bridge the bats can be heard chattering to each other before they take-off.
This is an awesome site. The bats are truly amazing. Probably the most incredible to me is how the moms find their way back to their very own baby bat who has been waiting patiently for dawn.
Several evenings later, we was sitting on my patio (a couple miles east of the bridge) that faces wests when a couple bats flew over, not unusual, then many, many more bats flew by! They probably fly by regularly, I just haven't been lucky enough to be outside at just the right time to see them. My cousins who were visiting got a double show, first at the bridge and then again at the home.