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Wildlife Protection

Keeping It Simple: Easy Ways to Help Wildlife Along Roads

A "fence" made of boulders keeps elk off a busy highway

Elk and other hooved ungulates can't navigate boulders without slipping off of them, so when Arizona Department of transportation environmental staff were looking for low-maintenance alternatives to elk fencing, they experimented with elk riprap along State Route 260's Christopher Creek Section. Large boulders were placed close together. Gaps were filled-in with smaller boulders hand-carried to the site by Arizona Game and Fish crews. So far, the riprap has proven as effective as fencing in deterring elk from getting onto the highway and into the path of oncoming vehicles. Instead of trying to cross the barrier, elk are following the boulders to nearby wildlife underpasses. And the slightly higher initial investment in the elk riprap will lead to significant savings long term.
--Mar 13, 2009

Bruce Eilerts, (602) 712-7398 or

This photo shows a line of large boulders with gaps filled in by smaller boulders. The "rock fence" leads to a wildlife underpass (not seen).
Photo by Photo by Arizona Game and Fish
This "fence" made of boulders works as well as standard wildlife fencing to keep elk off the highway.

Along Roads - Arizona
Updated: 12/12/2012
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