Tracking the nightly emergence and migration of millions of bats across Central Texas using NOAA NEXRAD weather radar — since 2011.
in the Significant Bat Area of Central Texas
Quantifications are calculated from a snapshot of maximum density, unless noted as emergence totals.
subtract 6:08 hours for CST of flights — 0:08 is about 6:00 pm CST
Check out our Congress Avenue Bridge page for the latest Congress flight times and viewing tips.
Scattered rain showers moving NE across Central Texas, Congress 0:10 on the edge of a rainstorm (Starting 22 minutes after sunset (as rain skirts past to the N), a snapshot at 6:29 pm showed 77,935 in flight - some heading 6 miles NW with most heading 8 miles SE (only 1% of the total at altitude) on NE Winds at 3 mph - had been northerly 5-8 mph most of the afternoon with Light Rain around 1:30pm, Mostly Cloudy, Temperature 63°F, Dew Point 56° steady, 3 Heating Degree Days, Cloud Base 1596', RH 78% rising, Heat Index N/A°F, BP 30.18 rising, Sea Level Pressure 1021.8 rising), Bracken 0:12, McNeil 0:14, Seguin Frio 0:24, Huber 0:28, other flights suppressed or readings confounded by weather
Above video from the evening of July 3, 2013 showing a seabreeze front from the SE and bats emerging from Central Texas roosts to feed on insects pushed along by the front.
When millions of bats emerge from a roost, they show up on weather radar. Austin Bat Refuge has been studying this phenomenon — called aeroecology — since 2011, tracking the nightly emergence patterns of bat colonies across the Significant Bat Area (SBA) of Central Texas.
Our data covers an enormous region — from San Angelo in the west to Round Rock in the north, New Braunfels in the south, and Del Rio in the southwest. This area includes dozens of known bat caves, bridge colonies, and migratory corridors.
The radar images capture what the naked eye cannot: the sheer scale of bat movement across the Texas sky, night after night, season after season.
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