BLM teams with researchers to protect midget faded rattlesnake

  • A large yearling midget faded rattlesnake found near its den in Rio Blanco County, Colorado.

    Joshua M. Parker

Summer snake hunting in western Colorado is a race against the sun. The reptiles emerge early from their dens to soak up dawn's dull warmth. But once the hillsides hum with heat, they'll split for the shadows. "We better get going," says biologist Josh Parker of Georgia's Clayton State University when I meet his small team of "herpers" in Grand Junction at 5 a.m. one June morning.

The three men -- Parker; Stephen Spear, a biologist with the Orianne Society, a Georgia-based reptile conservation group, who is clad in knee-high leather and nylon snake boots (equipped with 16 inches of "fang-deflecting armor"); and Arizona State University student David Vardukyan -- are a caffeinated whirlwind. Water bottles, snacks and maps fly like so much jetsam into an SUV stickered with rock-band decals. Its vanity plate reads "CONCOLR," an homage to the team's curious quarry: Crotalus oreganus concolor, the midget faded rattlesnake.

As its name implies, the midget faded is much smaller than most other rattlers, averaging 20 inches long, and its markings -- which resemble liver-shaped drops of dried blood -- pale over time. Edward Abbey once wrote that its "insulting name … may explain (its) alleged bad temper," a reputation more likely born of the species' potent neurotoxic venom, among the most powerful of any North American viper.

Midget fadeds are actually relatively docile and reclusive creatures, preferring creviced dens in rocky outcrops to burrows in open areas. Parker, who sports a graying tussock of chin whiskers and a silver barbell through one eyebrow, describes the snakes the same way you might afternoon tea -- "delightful."

Considered a sensitive species in both Wyoming and Colorado, the midget faded is increasingly threatened by energy development. Its range, which includes portions of Utah, Colorado and Wyoming, overlies rich oil and gas deposits and has areas crosshatched by wind farms. But there's been little research on how such projects affect the snakes. In fact, most of what's known about the species comes from Parker's dissertation on its Wyoming populations. That's something the herpers -- and the Bureau of Land Management, which has dispatched them -- hope to change.

As we head for the canyons beyond the city, Spear unfolds BLM maps marked with likely locations of midget faded dens and hibernacula, or winter shelters, for which we'll spend the morning scouting. Protecting dens -- which can house hundreds of snakes at once -- is key to preserving midget faded populations because they rely more heavily on them than do other rattlers, as communal areas during adolescence, gestation and other vulnerable life stages such as shedding, Spear explains.

The Colorado office of the BLM has been aware of the species' existence on the Western Slope since 2000, when a local natural gas boom was ramping up. But the snakes were so seldom encountered that they rarely came up as a management issue. Then, in 2010, a road-killed midget faded rattler, and later its den site, were found just a few meters from a well pad near Rangely. With the BLM's White River field office preparing for as many as 21,000 new wells in the surrounding Piceance Basin in the next 20 years, the agency knew it needed to find ways to protect the species. The data the herpers collect will help it guide development away from areas the snakes need most. After all, nobody -- not the BLM, the energy companies, nor the herpers themselves -- wants to see the midget faded decline enough to end up on the endangered species list, which comes with onerous land-use restrictions. Says Spear: "It impresses me that (the agency) is working on a species that doesn't bring in a lot of money and is often vilified."

The team's Colorado work is an extension of a Wyoming-based effort started in 2009. Wyoming's midget faded populations -- already struggling due in part to interstate and road building, as well as the submersion of habitat beneath Flaming Gorge Reservoir -- are restricted to a finger of habitat around the reservoir. With thousands of acres in the region now being considered for wind, oil and gas development, the Wyoming Game and Fish Department teamed up with Parker and Spear to map midget faded dens and key foraging areas, and determine how those places are connected in hopes of understanding and buffering possible impacts to the species.

Spear developed a GIS model that predicts probable den sites based on records of midget faded sightings; the snakes' narrow habitat needs, such as sandstone outcroppings; and other environmental variables like vegetation and elevation. Then he and Parker surveyed predicted sites to verify the model's results, identifying 12 new midget faded dens and collecting life history and genetic data from snakes encountered along the way. Their preliminary findings suggest that the dense networks of roads serving energy projects are a significant problem even if seldom used. Studies have found that just five cars per four hours will kill half the snakes trying to cross, blocking the creatures from key foraging grounds, which for midget fadeds can be as far as one kilometer from dens, and from mixing their genes with those of other families. Also, seismic surveying for oil and gas, which involves detonating underground explosives, may collapse dens.

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