March 27, 2008

Desert tortoises set for speedy transfer from tank site

The Press-Enterprise

Biologists will begin gingerly removing 770 desert tortoises Saturday from land the Army wants to use for tank training in the San Bernardino County desert.

"Every tortoise has to go quickly and gently to its new location," Kenneth Nussear, a research scientist with the U.S. Geological Survey, said about the reptiles threatened with extinction.

Nussear co-wrote a 129-page guide on how to delicately move the tortoises from an expansion area along the southern border of the Army's National Training Center at Fort Irwin, north of Barstow.

The $8.5 million effort, several years in the making and unprecedented in scale in California, is expected to take two weeks as the tortoises are moved a few miles south.

It culminates a 20-year battle pitting environmental groups against the military in what became known as tanks vs. tortoises.

The Army wants to expand its training grounds by 131,00 acres to accommodate faster-moving tanks and longer-range weaponry.

But some of that land is considered critical for the tortoises to survive. The decline of the reptiles, which have lived in the Mojave Desert for hundreds of thousands of years, has been blamed on disease, predation by ravens, habitat loss and off-roading, according to the U.S. Fish and Wildlife Service.

Congress eventually signed off on the expansion, offering up $75 million in 2000 to help protect the species.

The military will relocate the tortoises even though two environmental groups recently threatened to sue to stop the project. The Center for Biological Diversity and Desert Survivors filed a 60-day notice about two weeks ago, saying they were concerned the new habitat is lower-quality, has pockets of diseased tortoises, and is plagued by illegal dumping and off-roading.

Military environmental lawyers reviewed the group's claims and determined the effort can begin as scheduled, John Wagstaffe, a Fort Irwin spokesman, said Thursday.

Lisa Belenky, a staff attorney for the Center for Biological Diversity, said the groups were hoping to avoid going to court but will consider seeking an injunction to invalidate a permit issued by the federal wildlife agency that is allowing the move to go forward.

"We're only trying to make sure they're protected as best as they can be," she said.

Tortoise Hunt

Starting Saturday, biologists will scour the desert floor listening for radio signals to pinpoint the location of the tortoises, already outfitted with transmitters glued atop their shells. The moving crew will include a variety of state and federal biologists and a company contracted by the Army.
If the tortoises are in their burrows, the ground will be tapped to encourage them to emerge, and if need be, their shells will be gently nudged, said Roy Averill-Murray, desert tortoise recovery coordinator for the U.S. Fish and Wildlife Service.

"You can often retrieve them from burrows really easy and without causing a lot of stress by knocking on the front door," Averill-Murray said. "It doesn't always work but it sure is convenient when it does."

The reptiles can measure up to 15 inches from head to tail and weigh up to 15 pounds. They'll be placed into containers and moved in an air-conditioned vehicle or helicopter to their new habitat, which is mostly public land overseen by the U.S. Bureau of Land Management.

Once released, they'll be provided drinking water for 15 to 20 minutes, and then placed into an unoccupied tortoise burrow if available or in the shade of a shrub.

Tortoises must be moved carefully.

A frightened tortoise can squirt out all the water stored in its bladder, a move that can lead to dehydration and death, Averill-Murray said.

"They don't get a lot of chances to drink, so we definitely have to take precautions," he said.

Tortoises normally get their water from puddles that form during rain, or they will dig a small hole in the ground to collect water, Averill-Murray said.

"They have an amazing ability to suck up water in their nose from the ground or a rock," he said. "And if they can't get enough, they'll suck it up by eating mud."

Moving Preparations

The $8.5 million price tag covers several years of preparation, Fort Irwin spokesman Wagstaffe said.

Special mapping was done by the Redlands Institute, the research arm of the University of Redlands, to help scientists determine where to move the tortoises, said Lisa Benvenuti, the institute's resource manager.

Scientists don't want the tortoises moved too close to roads or to terrain with hard soil where they can't dig burrows. Places near power lines are also bad for the reptiles, because predators can perch above.

"You certainly don't want to put tortoises where ravens live. You're just giving them a snack," Benvenuti said.

The moving effort was delayed last spring because a lack of rain left the desert landscape with few plants for the tortoises to eat, Nussear said. The move must be made in the spring while the tortoises are still active.

The animals hunker into their burrows to escape the heat during the summer, he said.

Nussear, who helped relocate tortoises from housing developments near Las Vegas, said it takes about a year for them to become adjusted to their new surroundings.

"Each has its own requirements," he said. "When it finds a place it likes, it settles in."

He said the reptiles in Nevada did well after the move. They reproduced and had a survival rate as high as resident tortoises.

Researchers will monitor tortoises after they are moved from Fort Irwin, especially keeping an eye on an upper-respiratory disease found in tortoises in the expansion area and the new habitat.

The Army also wants to use land in Superior Valley west of Fort Irwin for tank training, so biologists will next figure out where and when to move those tortoises.

A relocation effort won't occur in the eastern expansion area where the tortoise numbers are so low it wouldn't be worth the effort, Averill-Murray said.