Supervisor Wants County to Take Over Bats’ Bridge

Orange County should take over a privately owned bridge, saving it from demolition and giving more than 1,500 bats a place to roost, a county supervisor said Monday.

Bat populations have fallen as development pushes into former wild lands, destroying their habitat, activists say.

Supervisor Bill Campbell, whose district includes the Hicks Canyon Haul Road Bridge spanning Santiago Canyon Road in northeastern Orange County, is facing an Oct. 1 deadline to preserve what has become a maternity ward for pregnant Mexican free-tailed bats.

“We want to keep that bridge from being demolished, and I’m optimistic that we will reach an agreement,” Campbell said.

The bridge was built eight years ago by an Alabama-based firm, Vulcan Materials, so its trucks hauling sediment from a dredging project could cross busy Santiago Canyon Road.

Part of the firm’s contract was to demolish the bridge once the work was completed.

If an agreement is reached with Vulcan and the Irvine Co., which owns the land, it will be a victory for the bats, said Stephanie Remington, a biologist who has studied the colony.

Bats typically have one baby per year, and it’s hard for them to recover from a population decline. Because they roost together, damage to one roost site can affect the entire population, Remington said.

Campbell and activists became concerned last spring when the bats were found roosting in the dark hollows of the structure. At that time, the plan was to remove the bridge in June, which would have perhaps killed hundreds of young bats, activists said.

Instead, the county granted a delay until October when the bats’ breeding season was over.

When temperatures drop, Mexican free-tailed bats migrate to Mexico’s northern states for the winter. But Remington said she believed the colony didn’t migrate. “They seem to like the Southern California weather,” she said.

The engineering firm that built the bridge could face additional permit fees if it does not meet the October deadline. Vulcan has submitted an application for a demolition permit. But approval is on hold, said Herb Nakasone, the county’s public works director.

Public works staff members also are studying whether the bridge needs retrofit work to ensure the public’s safety if the county takes it over, Nakasone said.

The bridge also is a habitat for smaller Yuma bats, which, like their bat cousins, feed on insects such as mosquitoes.

Yuma bats’ body temperature drops in winter and their heart rate decreases, but not much is known about their winter activities, Remington said.

“We don’t have bat caves here in Southern California where they can be studied,” Remington said.

Activists said they also want the bridge to become part of the county’s trail system, providing a safe passage over Santiago Canyon Road for joggers, hikers and mountain bikers.

“This bridge was designed for gravel trucks,” Campbell said. “And if the county takes it, we’re talking about joggers and bicyclists going over it so it will be able to handle that.”