May 2005, Volume 3, Issue 5

Saving a Bat Bridge


More than 1,500 Mexican free-tailed bats have turned a private bridge in Orange County, California, into a nursery. The problem is that the Hicks Canyon Haul Road Bridge across Santiago Canyon was scheduled for demolition. Now the bats and their home will be spared, reports the Los Angeles Times.

County Supervisor Bill Campbell, local activists, several agencies and the bridge owner spent much of the past year negotiating a plan to save the structure.

“Keeping the bridge will be a good thing,” Campbell told Times reporter David Reyes. Bats use the bridge year round, and humans – especially outdoor enthusiasts and cycling groups – also make use of it. Their support was critical to the agreement.

The bridge was built nine years ago by Alabama-based Vulcan Materials so that its trucks hauling sediment from a dredging project could cross busy Santiago Canyon Road, the newspaper said. The contract required destruction of the bridge when the work was completed.

Then a colony of pregnant bats was discovered under the bridge last year. “We did some research to determine what the maternity period was and decided to wait [to] allow the mother bats to give birth,” said Vulcan Vice President Steve Cortner.

Then, of course, the baby’s were born, so demolition was delayed again, with the help of Campbell and activists.

According to the preliminary agreement, the Times reports, Vulcan will sign over the bridge to the county and pay $95,000 for retrofitting costs the county might face. Campbell said he wanted the county to receive a portion of what the contractor saves by not having to demolish the bridge. The bridge meets Caltrans construction standards for a temporary bridge and has withstood hundreds of loaded gravel trucks, Cortner said.

In the fall, when temperatures drop, Mexican free-tailed bats usually migrate to Mexico’s northern states for the winter. But local biologists say the bridge colony seem to like Southern California’s mild weather and generally remain in the area all year. Now they’ll still have a place to stay.

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