Agency officials felt Spear's model might offer a way forward in western Colorado as well. Often, BLM surveys simply determine areas appropriate for development based on a species' presence or absence -- with protected habitat determined by a line drawn around areas where the creature has been spotted. But that method tends to miss important habitat features like den sites, Spear explains, while unnecessarily "including a lot of areas that are not good habitat," where energy could safely be developed.

Spear's model provides more precise data that will make planning and mitigation measures more effective, says White River field office spokesman David Boyd. Companies hoping to develop in probable snake habitat will be required to survey for the species prior to any surface disturbances and to avoid possible hibernacula or den sites by up to 660 feet. Companies will also be required to manage infrastructure in ways that reduce the risk of killing snakes, including gating roads to allow only well-pad traffic, says Boyd.

At a narrow canyon footing a rocky slope, Parker pulls the SUV over. We smear on sunscreen, swig water and grab gear, including mammoth metal pincers that resemble something a giantess might use to pluck her eyebrows -- "snake tweezers," Vardukyan says.

The standard search procedure is to spread out evenly and walk for one hour in a straight line, looking for snakes and their traces: a shed skin or sinuous scribble in the dust. When someone spots a faded midget, the team takes a GPS location and grabs and bags the serpent (with the snake tweezers, of course). Back at the truck, they coax the creature into a tube so they can safely measure and weigh it, estimate its age, determine its sex and reproductive condition, and count its rattles. They also take a blood sample for the species' genetic archive, and a venom sample for a Colorado biologist investigating the neurotoxin's potential biomedical applications (compounds in Gila monster venom, for example, are used to treat diabetes) and the genetic differences between closely related rattler species.

By the end of the summer, the team will have found evidence of 22 dens, including 18 live and three road-killed midget fadeds and one shed skin. They will use this information to refine the model when they ground truth it in summer 2014.

But we don't hit pay dirt until the second morning of our hunt, in an area where Spear's model predicts dens. As the mesas begin to blush pink, we set out across what seems like the perfect midget faded haunt: a south-facing bank, crowned in rocky outcrops and flanked with sandstone slabs. Still a novice at searching out venomous snakes, I gleefully -- and heedlessly -- push my face into rock shadows and under ledges as if nosing out a lost shoe.

"Hey! I got one!" Parker calls out as the rest of us stumble back across the slope to converge on his find. "Be as quiet as possible and give it space," Parker says as we whisper cameras from pockets. "Where is it?" I ask.

"Just below that slab of sandstone," Spear says, pointing.

"Where?"

"Right there!" the men say in unison. Finally, my search pattern resolves, and where there was nothing but sun and sand there now lies a piffling puddle of snake, hunkered and still as a carving. Parker guesses it is a male, between 3 and 5 years old.

"It's sleeping," he says. Moving closer, I'm startled to find its needle-slit eyes staring back at me. "They sleep with their eyes open," Parker explains, sensing my hesitation. "If it was awake, it'd be tongue-flicking, trying to smell us." Reassured, I lean in again, camera ready. But it's too late; the statue sparks to life and bolts past my left knee. I scream and leap down the slope, heart in my stomach.

"Don't worry," Spear says, between chuckles. "It wasn't coming at you; you just happened to be between it and its hidey hole."

"Poor little guy," Vardukyan says, shaking his head.

Parker nods. "You really scared it."

He points to a juniper where the snake has sought refuge in a snarl of roots. The faded midget peers up at us and rattles out its warning song, the bone-dry purl of a living rain stick.