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Wildlife Protection

Keeping It Simple: Easy Ways to Help Wildlife Along Roads

Using Gravel to Unblock Desert-Tortoise Culverts

Desert tortoises, federally-listed as a threatened species, got a lucky break recently in San Bernardino County, California. When California Department of Transportation (Caltrans) biologists noticed construction riprap was preventing desert tortoises from using culverts next to an Interstate 15 widening project, they remedied the situation with a quick and easy solution: gravel. To keep tortoises near the culverts from falling into the holes between the riprap, Caltrans crews poured gravel into the holes, filling up the spaces between the rocks. Then they spread the gravel to make a flat, even surface. According to Caltrans' monitoring studies, desert tortoises using the culverts are moving along the "new and improved" surfaces just fine.
--Aug 21, 2006

Mahmoud Sadeghi, (951) 383-6386 or

close-up of a desert tortoise
Caltrans photo
The desert tortoise.

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Along Roads - California
Updated: 12/12/2012
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