Biologists scour Mojave in desert tortoise roundup
More than 100 biologists and contract workers fanned out across a nearly pristine stretch of the eastern Mojave Desert on Friday to start rounding up tortoises blocking construction of the first major solar energy plant to be built on public land in Southern California.
On a sunny morning in the height of tortoise courting season, the biologists methodically peered under every bush and into every hole on both sides of a two-mile lane traversing the project site. Following close behind, workers bladed century-old creosote bushes and erected fencing in areas that will soon be declared a “tortoise-free zones.”
The effort in San Bernardino County’s panoramic Ivanpah Valley, just north of Interstate 15 and about 40 miles southwest of Las Vegas, disrupted complex tortoise social networks and blood lines linked for centuries by dusty trails, shelters and hibernation burrows.
Federal wildlife biologists said it was needed to make way for construction of BrightSource Energy’s 3,280-acre, 370-megawatt Ivanpah Solar Electric Generation System.
Without the roundup, an estimated 17 federally threatened tortoises — and an unknown number of half-dollar-sized hatchlings — in the 913-acre initial phase of the project would have been squashed by heavy equipment.
A total 36 adult tortoises are believed to inhabit the project site. “We can never say we got them all out of there — these are cryptic creatures,” said Roy Murray of the U.S. Fish and Wildlife Service desert tortoise recovery office.
Under a plan approved by the U.S. Fish and Wildlife Service and the U.S. Bureau of Land Management, as many tortoises as possible will be captured, weighed, measured, photographed, blood tested, fitted with radio transmitters and housed in quarantine pens with artificial burrows.
The tortoises will remain in the pens until they can be transported and released in natural settings elsewhere in the region determined to be free of disease and predators — a process expected to take several months.
Tortoise translocation is still an experimental strategy with a dismal track record. In previous efforts, transported tortoises have shown a tendency to wander, sometimes for miles, often back toward the habitat in which they were found. The stress of handling and adapting to unfamiliar terrain renders the reptiles vulnerable to potentially lethal threats: predation by dogs, ravens and coyotes; respiratory disease, dehydration and being hit by vehicles.
But project biologist and tortoise expert Mercy Vaughn was optimistic.
“Our goal is zero kill,” Vaughn said. “I feel a lot more positive about this relocation project than any other I have been involved with or heard about. That is because these animals will be transported less than a half-mile away. So they will still be within their home range, or near it.”
Vaughn added, “The extraordinary effort unfolding here today is a measure of our commitment to this animal, which is a federally listed species and emblematic of the desert. It is also our state reptile.”
Brightsource’s project will rely on hundreds of mirrors known as heliostats to focus the sun’s rays on the tops of 200-foot towers, where water boilers will produce high-pressure steam to run electric turbines.
The development of solar power facilities in the desert has been a top priority of the Obama administration as it seeks to ease the nation’s dependence on fossil fuels and address climate change.
Several alternative energy companies are racing to finalize permits and break ground by the end of the year, which would allow them to qualify for federal stimulus funds. At stake are thousands of jobs and enough energy to power almost 1.8 million homes, according to federal land managers.
The California desert tortoise population has fallen to an estimated 33,000 on public lands in the northeastern Mojave Desert. Some environmentalists fear that the development of large-scale power plants will hasten the demise of Gopherus agassizii, which live a century and spend most of their lives underground.
“It is complete hubris for anyone to say you can save a species by removing it from its habitat,” said Janine Blaeloch, director of the Western Lands Project, a nonprofit Seattle organization dedicated to preventing privatization of public lands. “This is the beginning of the industrialization of this site, and the irreversible transformation of its ecosystem.”
Vaughn agreed, up to a point. “Since we have declining numbers throughout the Mojave Desert, every individual tortoise matters,” she said.