Kern County may require a major developer in its growing wind energy sector to track the radio signatures of California condors and shut down wind turbines if they threaten the endangered birds.
As the species rebounds from near-extinction, county environmental reports state, condors are expanding their foraging territory outside of their nesting areas in the Tehachapi Mountains.
It is possible that the birds may fly over the fields of 500-foot-tall wind power towers, coming dangerously close to blades spinning at deadly speeds.
On Tuesday, Kern County supervisors will be asked to approve the newest proposed phase of the massive Alta Wind project northwest of Mojave; a 2,592-acre Alta East project near the intersection of Highways 58 and 14.
Approval, said Kern County Planning Director Lorelei Oviatt, would include the requirement that Alta developer Terra Gen-Power establish a system for monitoring the radio signals from condors and shut down turbines if the birds get close to them.
Only 568 acres is on private land under Kern County's jurisdiction. But Oviatt said the county has worked with the Bureau of Land Management -- which owns the other project property -- to establish the safeguards for the condor.
The system, which has had some successful tests, according to county reports, could sense the birds up to 16 miles away from the development and track their flight.
If a condor flies too close, Oviatt said, the person monitoring the signals could selectively shut down turbines. Blades would stop spinning in around one minute, she said.
This is, Oviatt said, the second time Kern County has required a developer to use the technology, the first being on the Avalon Wind project approved in December.
While the system has not been installed in any Kern County wind energy projects, county reports indicate the system was tested over three days in July at the Bitter Creek Wildlife Refuge and had a 100 percent detection rate.
"In every case the VHF detection system recorded a condor occurrence before the human observer could detect it and in many cases, detected the occurrence of a condor that a human observer did not detect," wrote county planning staff in response to questions from the environmental group the Center for Biological Diversity.
Lisa Belenky, an attorney for the Center, said there is value in any attempt to protect the condor species.
"Certainly it's better than nothing, which is what they've done on other projects," she said. "We have data of condors moving in quite close by not only to this project but to other projects as well."
The Center has, in the past, challenged the wisdom of Kern County's wind energy development decision, pointing to the threat to condors and other bird species. And it raised concerns about the Alta East project as well.
Belenky said the Center still has questions about the proposed monitoring plan.
"We don't know how well the system will work. We're very hopeful that it would be a good measure to prevent an impact to condors," she said. "We are somewhat concerned because even now not all the condors have the radio tags on them."
And the program does not protect other bird species who are not tagged with radio locators, Belenky noted.
It also, she said, does not require developers to do the same kind of monitoring on projects that have already been approved, built and are already operating in Kern County.
"They should also look at requiring this of existing projects," Belenky said.
Oviatt said the county has, indeed, reached out to developers of approved projects to assess the possibility.
She said the county has learned a great deal as it has considered and approved wind energy projects here over the past few years and is adopting what it has learned in proposing the condor tracking program.