Around sunset, the underside of the Waugh Drive bridge over Buffalo Bayou starts to stir. Then Mexican free-tailed bats begin dropping out of the crevices, first a few, then a dark ribbon that twists along the bayou and rises over the trees. Buffalo Bayou Partnership, which manages the colony for the city, puts the summer population at roughly 300,000, the largest bat colony in Houston. Unlike many Texas colonies that leave for Mexico in the fall, these bats have been found under the bridge in every month of the year, though nights below about 50 degrees can keep them roosting. Each one can eat up to two-thirds of its body weight in insects in a night and may fly more than 60 miles round trip. Watch from the observation deck at Allen Parkway and Waugh Drive, or look down from the bridge itself. On spring and summer evenings, hawks sometimes work the edges of the swarm.
What to expect
- Don't stand under the bridge as the bats come out; droppings rain down.
- No camera flash or phone flashlight, and keep voices low while they fly.
- The flight lasts a few minutes to half an hour; bring bug spray and water.
- Viewing from the deck and the bridge sidewalk is wheelchair accessible.
- Rain can keep the bats in the bridge, though you may still hear them.
What to do
- Stake out a spot on the observation deck at Allen Parkway and Waugh Drive 30 minutes before sunset
- Watch the emergence from atop the Waugh Drive bridge as the column forms below you
- Book a Buffalo Bayou Partnership bat colony boat tour ($30) to see the flight from water level
- Mexican free-tailed batSpecies
- About 300,000 batsSummer colony
- 60+ miles round tripNightly range
- Up to 2/3 of body weight a nightAppetite