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Wildlife Protection

Keeping It Simple: Easy Ways to Help Wildlife Along Roads

Turning a box culvert into a bat culvert

A Texas Department of Transportation Bats and Bridges Study recognizes how bats benefit society by preying on flying pests and crop-eating insects. According to the study, more bats are likely to inhabit culverts in Webb County, Texas, than in any other county in the state. So in 1999, Department engineers modified plans for a drainage culvert under U.S. 83 in Webb County to Include bat roosts. The new design called for five recessed, square "domes" built into the ceiling of the culvert and a rough-textured roosting surface made with recycled plywood forms. The culvert, now built, houses about 200 Mexican free-tailed bats and may house as many as 200,000 bats once the species becomes familiar with the roosts. Retrofitting the culvert was easy, and planning ahead saved taxpayers more than $300,000.
--Apr 25, 2003

Melissa Montemayor, (956) 712-7456 or

Entrance to box culverts containing "bat domes"
Photo by Mark Alvarado, Texas Department of Transportation
"Bat-dome" culvert on San Idelfonso Creek at US 83

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Along Roads - Texas
Updated: 12/12/2012
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