October 10, 2008

Fort Irwin suspends tortoise translocation

By Abby Sewell
Desert Dispatch

FORT IRWIN • Fort Irwin will not be moving desert tortoises as planned this fall, partially in response to a lawsuit by two environmental advocacy groups.

The U.S. Army began transferring tortoises from an area slated for inclusion in a 118,674-acre expansion of the post in the spring. Since then, researchers working for the Army have been using transmitters to track 411 of the 556 tortoises moved from the southern expansion area, said Roy Averill-Murray, desert tortoise recovery coordinator with the United States Fish and Wildlife Service, which is working with the Army on the project.

Of the tortoises that were tracked, Averill-Murray said that 80 or 90 have died, many of them falling prey to coyotes. The wildlife service stated in its biological opinion on the moving process that no more than 136 of the translocated tortoises should die.

“We’re getting close to that number, and we still have the entire western expansion area to look at,” he said, referring to a second, larger, group of tortoises originally scheduled to be moved in the spring.

The Center for Biological Diversity and Desert Survivors filed a federal lawsuit against the U.S. Bureau of Land Management and the Department of the Army in July, alleging that the agencies failed to conduct extensive enough environmental review before transferring the tortoises. Averill-Murray said that the lawsuit was largely the impetus behind suspending the translocation.

The Army had originally planned to move 40 or 50 more tortoises out of the southern expansion zone this fall, Averill-Murray said. Fort Irwin spokesman John Wagstaffe said that will be postponed for an unknown period, meaning that the post will be unable to start using the area for training exercises as planned.

It also appears unlikely that the transfer of the tortoises from the western expansion area will go forward in the spring, Averill-Murray said.

Researchers will attempt to determine an accurate tortoise population figure for the western expansion area, to assess alternative habitat areas for the tortoises, and to more fully understand how many of the deaths among moved tortoises were related to the removal of the animals from their original habitat.

Averill-Murray noted that coyote predation has risen throughout the Mojave Desert, possibly due to a drought in the region that led to a decline in populations of some of the coyotes’ other natural prey.

Center for Biological Diversity biologist Ileene Anderson counted the suspension of tortoise transfer as a victory. The Center wants to see a less-trafficked area chosen for the tortoises’ new habitat, to minimize dangers from dogs and off-road vehicles, and a higher level of protection for moved tortoises, including possibly fencing their habitat, she said.