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Clay Noss has joined the Nicholas School of the Environment as a lecturing fellow in the Environmental Natural Sciences Division. Noss is also conservation coordinator for the Desert Tortoise Recovery Partnership, an effort to protect a species of tortoise living in California’s Mojave Desert.

“I’ve always been obsessed with reptiles and amphibians,” says Noss, who spent part of his childhood in Oregon. At around age 8, he took a public class on herpetology — the study of reptiles and amphibians — offered by a local university. “That’s when I learned that being a herpetologist was a [career] possibility,” he recalls.

Later, while pursuing a wildlife ecology degree at the University of Florida, Noss spent a summer interning with the U.S. Fish and Wildlife Service in Arizona. On his drive back east, he detoured into , a sprawling field of gypsum sand dunes punctuated by scrubby vegetation, in New Mexico. Rising like an island in the Chihuahuan Desert, the pale dunes comprise a unique ecological haven for three species of desert lizard, among other creatures.

“I said, that’s where I wanted to do my Ph.D. [research], because it was so beautiful, and the lizards were so interesting,” says Noss, who earned his doctoral degree from the University of California, Berkeley.

White Sands lizards have evolved with few predators or other threats, enabling their populations within the park to balloon. For his dissertation, Noss explored how this unique ecosystem has shaped White Sands lizard populations compared to lizards living in surrounding desert scrub or at the border of the dunes and scrub.

Using several analytical methods, Noss learned that lizards in White Sands had more specialized diets than lizards at the dune border and beyond. Even within a single population, White Sands lizards appeared to partition resources to a much higher degree than their counterparts, he says.

“It’s probably due to the higher competition between individuals paired with the lower prey diversity in White Sands,” explains Noss, who published part of his in Oecologia last January.

The findings show how environments with few species can promote different survival strategies within a species — a phenomenon that could be responsible for much of the biodiversity we see today, Noss says.

As a postdoc at the University of California, Riverside, Noss shifted focus from White Sands lizards to Mojave desert tortoises, listed as threatened under the Endangered Species Act. There, he analyzed the efficacy of a “head start” program for juvenile tortoises — a tortoise tot day care, of sorts.

“Especially in turtles, the mortality [rate] for babies is really high. So, the idea is, you take eggs, hatch them in [burrow-like] enclosures, raise them until they’re a little bit bigger, and then release them [into the wild].”

Noss and colleagues found that turtles that spend more time outside their burrows are more likely to die from predation. The finding highlights a risk associated with human encroachment into southwestern deserts: more predators.

“We [humans] provide trash, and that trash artificially inflates the populations of ravens and coyotes, which translates into higher predation levels for some organisms like the desert tortoise,” Noss explains.

Noss’s postdoctoral research now informs his work as coordinator for the Desert Tortoise Recovery Partnership, established in 2020 by the U.S. federal government. His role is to facilitate collaboration and evaluate tortoise  across federal and nongovernmental partners. 

“The coordinator position has been fun, because I get to meet with people, and talk to people more, and really help deliver for the tortoises,” Noss says.

Tortoises have also taken center stage during his inaugural seminar at the Nicholas School. For the past semester, Noss has taught students enrolled in the Nicholas School’s Master of Environmental Management program about wildlife conservation science, policy and management through turtles, snakes, frogs and, of course, lizards.

Noss will also use reptile and amphibian case studies in a statistics course he plans to teach next semester. Through these real-life examples, the lessons might stick better, he says.  

“I’ve always loved lizards. I didn’t initially enjoy stats, but the lizards made me love the numbers because of what they can tell me about lizards.”