Austin's most spectacular natural wonder. The largest urban bat colony in the world — and Austin Bat Refuge has been your trusted guide here for over a decade.
Up to 1.5 million Mexican free-tailed bats · Every evening March–October · Free to watch
Our normal (start of) Flight Time prediction for Thursday, July 9, 2026 is between
Given that winds stay low, little chance of rain, and afternoon temperatures are over 65°F — CHANCE FOR A GREAT FLIGHT TONIGHT.
Given the right conditions, bats will likely emerge between sunset and dark. Bats can sometimes burst out a half hour earlier on warm North winds, so get there early on those evenings. Temps below 60°F, non-northerly winds over 10 mph, good rain chances, or a waxing gibbous to full moon can suppress or diminish flights.
Updated daily by Austin Bat Refuge staff · July 9, 2026
Beneath the Ann W. Richards Congress Avenue Bridge lives a colony of approximately 1.5 million Mexican free-tailed bats (Tadarida brasiliensis) — the largest urban bat colony in the world and one of the most awe-inspiring wildlife spectacles on the planet.
Each evening from March through October, the bats pour out from the bridge's expansion joints in a swirling, undulating stream that can last up to 45 minutes. Mothers and pups reunite in mid-air. The sky darkens with wings. It is, simply, unforgettable.
Austin Bat Refuge is the only organization with up-close experience at this site. We've staffed the public education table at the bridge every Friday, Saturday, and Sunday — rain or shine — for years.
Emergence begins near sunset. Arrive 30–45 minutes early.
| Month | Approx. Emergence | Colony Size |
|---|---|---|
| March – April | 7:30 – 8:00 PM | Arriving / Growing |
| May – June | 8:15 – 8:45 PM | ~1 million |
| July – August | 8:00 – 8:30 PM | ~1.5 million |
| September | 7:30 – 8:00 PM | ~1.5 million |
| October | 7:00 – 7:30 PM | Departing |
The same species that fills the Congress Avenue Bridge every evening — filmed in flight. One and a half million emerge each night in a stream that lasts up to 45 minutes.
All three spots are free, family-friendly, and within 100 yards of each other. You cannot get a bad view — pick the one that fits your group.
The closest view — bats emerge from expansion joints directly below your feet. Stand at the east railing for the best angle as the colony heads northeast. Fills up fast; arrive early on weekends.
A dedicated lawn below the bridge on the south bank of Lady Bird Lake. More relaxed, great for families with blankets and folding chairs. Our education table is here every Fri–Sun.
Several operators launch bat-watching boats and kayaks from the Congress Avenue dock. Watch a million bats swirl overhead from the water — an unforgettable perspective.
Seven evenings of field observations from Austin Bat Refuge staff at the bridge.
| Date | Emergence | Duration | Conditions | Quality | Notes |
|---|---|---|---|---|---|
| Sun, May 11 | 8:08 PM | 38 min | 71°F · Clear · SE 6 | Excellent | Full flight, large crowd |
| Sat, May 10 | 8:06 PM | 42 min | 68°F · Clear · S 5 | Excellent | Perfect conditions |
| Fri, May 9 | 8:10 PM | 35 min | 74°F · Partly Cloudy · SW 10 | Good | Strong flight despite wind |
| Thu, May 8 | 8:12 PM | 28 min | 77°F · Hazy · S 12 | Fair | Shorter emergence |
| Wed, May 7 | - | - | 61°F · Rain · NW 18 | No Flight | Storm cancelled emergence |
| Tue, May 6 | 8:08 PM | 40 min | 69°F · Clear · SE 7 | Excellent | Outstanding night |
| Mon, May 5 | 8:11 PM | 31 min | 72°F · Clear · S 9 | Good | Average crowd for Monday |
Austin Bat Refuge staff record conditions each evening from the bridge viewing area. Data is updated each morning.
Our education table at Congress Avenue Bridge is staffed entirely through donations. Help us keep the wonder alive.
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