TWENTYNINE PALMS, CALIF. — Troops sent to the Marine Corps’s sprawling base in the Mojave Desert near here for advanced combat training are warned sternly about an unbreakable rule: no harming the desert tortoises or leaving behind food crumbs that are likely to attract ravens, the arch-predator of tortoises.
To further protect the creatures with the high-domed shells on their backs, certain areas of the base are off-limits. And to prop up the tortoise population on base, the Marines have teamed with UCLA for the past decade to run an on-base hatchery.
Yet a battle is brewing between the Marines and the tortoises — or, really, their environmental advocates — that shows how even a fast-moving fighting force must sometimes give way to some of the slowest creatures on Earth.
The issue is a live-fire exercise set for August to train troops in assaulting an enemy from numerous locations. Similar exercises have been done in the past, but this year’s event was to have included recently annexed property that is home to numerous desert tortoises.
To protect the tortoises from becoming collateral damage as bombs, mortars and artillery are fired and Humvees rumble around, the Marines were planning to airlift more than 1,100 of them away from the area.
But just weeks before the relocation was to begin, the Center for Biological Diversity in Tucson protested that the effort would mean certain death for large numbers of the tortoises, in violation of the Endangered Species Act. The group warned that it would go to court to stop the operation.
As a result, the airlift is on hold, the training exercise has been downsized and federal officials not aligned with the Marine Corps are reviewing the tortoise relocation to judge its impact on the creatures.
“This proposed translocation is a disaster for the already at-risk desert tortoises in the west Mojave Desert,” said Ileene Anderson, a senior scientist with the diversity center.
The desert tortoise is found in the Mojave and Sonoran deserts of California, Nevada, Utah and Arizona. An adult tortoise can reach six inches in height, weigh up to 15 pounds, and live as long as 100 years. The tortoise population in the western Mojave, which includes the Marine base, has declined by 90 percent since the early 1980s, according to the advocacy group Defenders of Wildlife.
Among the causes cited by the group and others for the decline are drought, respiratory disease, a population explosion among ravens, suburban development and increased use of the desert by off-roaders and other recreationalists.
In response to the environmentalists’ concerns, the Marines say they have carefully monitored the health of tortoises set to be relocated and will continue to do so through small transmitters on the animals’ backs. The Corps has allocated $50 million for the airlift, environmental assessments, fencing, research and health monitoring of the tortoises through the year 2045.
“We’re not just going to throw them over a fence,” said Walter Christensen, natural and cultural resources branch manager at the base. Six spots adjacent to the base have been assigned for the relocation, he said. All have sufficient water and food and are far enough away from the tortoises’ current homes that they will not try to walk back, he said.
At 1,190 square miles, the Marine base is nearly the size of Rhode Island. Most Marines sent to Iraq and Afghanistan come here for training, under a program known as Mojave Viper.
Faced with the possible lawsuit over the tortoise airlift, the U.S. Fish and Wildlife Service announced that it was reviewing its tentative approval of the relocation plan. Since the desert tortoise is listed as a threatened species — a notch below endangered — the service’s approval is needed for any such move.
The Marines have reconfigured and downscaled the August training away from tortoise-heavy areas, with fewer tanks and armored vehicles. In addition, no live-firing will be done in Johnson Valley, an area of the base that is central to the dispute.
Training is an everyday event at the base, located 140 miles east of Los Angeles. But the August exercise was meant to be special: It was to be the first time that the Marines used the Johnson Valley property, Marine brass hoped to find out whether the valley would be good not just for large-scale exercises such as this summer’s but also for even larger exercises in coming years.
For a decade, the Marines fought environmental groups, local landowners and off-road enthusiasts over annexing Johnson Valley, which was controlled by the federal Bureau of Land Management.
In 2013, after intervention by Sen. Dianne Feinstein (D-Calif.), a deal was cut by Congress: 107,000 acres of Johnson Valley will be designated exclusively for use by the Marine Corps, another 50,000 will be shared between the Marines and civilians. The August exercise is to include sections of both, as well other areas of the base.
The Marines insist they need to use the property to devise a training exercise in which three large infantry groups can practice assaulting a common target, each using artillery, mortars and air power. Without the Johnson Valley area, the corps has no base large enough for such an exercise, officials said.
At the crux of environmentalists’ concerns was a tortoise relocation done in 2008 at the Army’s Fort Irwin, which is east of Twentynine Palms. That program was suspended after only a year when it was learned that about 30 percent of the relocated tortoises had died.
“It was a debacle,” Anderson said of the Fort Irwin program.
To the Center for Biological Diversity, that experience shows that relocation is a dreadful strategy and that the Marines’ plan, which would involve many more tortoises,needs further scrutiny.
The Marines assert that the Fort Irwin deaths are misleading. Brian Henen, a civilian ecologist at the Twentynine Palms base, said the mortality rate of the tortoises that were moved was the same as that of tortoises that were not relocated, suggesting the main cause was a drought that decreased water and forage. Federal officials, who did an investigation of the Fort Irwin deaths, also concluded that the deaths most likely were attributable to the drought. Environmental groups disputed the finding.
Brian Croft, a wildlife biologist and division chief with the Fish and Wildlife Service, has sympathy for both sides in this dispute. His agency has dealt with numerous problems related to the moving of tortoises, including ones caused by solar projects and a community college expansion next to the Twentynine Palms base.
“From everything we know from studying translocation, as long as it’s planned properly, it can be done without increasing the mortality rate of the animals,” Croft said.
The Fish and Wildlife Service expects to decide in September whether the Marines can go ahead with the airlift, Croft said.
Jennifer Loda, the Center for Biological Diversity’s attorney for amphibian and reptile issues, said she hopes the final decision will leave the desert tortoises undisturbed. The tortoise’s ancestors lived in the Mojave Desert thousands of years before the Army and Marine Corps arrived, she noted.
“They have an inherent right to be here. They have the same right as we do.”