Defenders’ renewable energy and wildlife policy associate, Pasha Feinberg travels in search of the mysterious Agassiz’s desert tortoise.
I arrived in the heart of the Mojave Desert just in time to witness it in bloom. The golden and sage landscape lay peppered with the fuchsia, yellow, and purple bursts of cactus flowers. This breathtaking show of color and life in the middle of North America’s driest desert draws countless visitors each year, but although the display was stunning, I was in search of a less conspicuous desert denizen: Agassiz’s desert tortoise.
My journey began in my office in Washington, D.C., with a call to travel west and meet with officials at the Bureau of Land Management (BLM). These agency staff are charged with approving and overseeing much of the renewable energy infrastructure built in the Southwest and I was sent to discuss solar energy projects slotted for areas in the Mojave Desert—the only place in the world where these tortoises live. We discussed strategies to appropriately site renewable energy projects while still protecting important habitat for desert tortoises.
After discussing options with the BLM to ensure a better future for the desert tortoise, it was time to actually see some. Luckily, if the tortoises proved too elusive, I had an ace up my sleeve—I’d been granted access to the National Park Service’s Ivanpah Desert Tortoise Research Facility.
The Ivanpah Desert Tortoise Research Facility was built a stone’s throw from the Mojave National Preserve in prime desert tortoise habitat, a fact confirmed as I drove towards it and spied a basking tortoise! After carefully encouraging the tortoise off the road (you don’t want to pick up and scare tortoises, which may cause them to pee and lose precious water), I headed into the facility to learn more about these charismatic critters.
Diving Headfirst into Headstarting
The desert tortoise spends the vast majority of its long life—they can live up to 80 years!—in underground burrows, hibernating in the winter and avoiding the scorching desert sun in the summer. Although its brown and gray color helps it blend seamlessly into its environment when above ground, desert tortoises weren’t always so hard to find. A variety of factors have caused their numbers to decline, including habitat loss from development and agriculture, military training, grazing, roadkill, disease, and predation.
Even with the U.S. Fish and Wildlife Service’s listing the tortoise as a threatened species under the federal Endangered Species Act, threats persist and the tortoise population continues to decline. Exacerbating existing problems are increasing desert development, poorly sited energy projects, off-road vehicle use, and high juvenile mortality.
In an effort to bolster the wild population of desert tortoises, Professor Brian Todd from University of California, Davis and Drs. Tracey Tuberville and Kurt Buhlmann from the University of Georgia’s Savannah River Ecology Laboratory set up the Ivanpah Desert Tortoise Research Facility to provide a safe space for tortoises to grow before being released into the wild.
Upon entering the facility’s grounds, I immediately notice the four outdoor enclosures, complete with native Mojave vegetation, sprinklers, artificial burrows (with plenty of room for tortoises to dig their own), and an overhead net to keep out ravens.
Although adult desert tortoises have few natural predators, baby tortoises are easy prey and few survive past their first year. Ravens are a leading tortoise predator and human development in the Mojave provides the birds with plenty of food, water, and perches. Even though ravens have always been in the desert, because of this development, their numbers have skyrocketed in recent years.
“Juvenile tortoises are like raviolis to ravens,” explains Mark Peaden, a PhD student at UC Davis. Mark is conducting his dissertation research at the Ivanpah Desert Tortoise Research Facility and has generously agreed to show me around.
Along with his fellow researchers, Mark works at the facility with the dual purpose of “headstarting” tortoises and exploring their ecology. It’s in these outdoor enclosures, he explains, that most of the facility’s headstarting is conducted.
Headstarting is the process of protecting animals during particularly vulnerable life stages to increase the likelihood of…