SARATOGA — Sage grouse spotted ahead, and the chase was on.
"Thirty meters!" shouted ecologist Jon Kehmeier. He throttled the gas.
Five of the mottled brown, chicken-sized birds appeared in the headlights, strutting through the dry, knee-high grass.
Ecologist Nate Wojcik jumped out, ran and swung his fish net gently atop a young female, first of the night to be fitted with a location transmitter.
Nowhere else are sage grouse as plentiful as they are in Wyoming. Nowhere else do they face as much potential habitat loss amid oil and gas drilling and wind farm development.
Next year, the U.S. Fish and Wildlife Service must decide whether to protect the greater sage grouse as a threatened or endangered species. A federal listing could impede energy development on this energy hub state's vast sagebrush expanses.
One major energy project is tackling the quandary head-on.
People are also reading…
At the biggest wind farm project in the U.S., the Chokecherry-Sierra Madre development in south-central Wyoming, developers say they want to help their local population of greater sage grouse despite any listing.
Four years of research, which includes the night patrols, is helping to determine where roads and many of the up to 1,000 turbines will go.
"We have the most robust data set, I think, anyone has generated for sage grouse," said Garry Miller, vice president of the Power Company of Wyoming, the Denver-based Anschutz Corp. subsidiary developing Chokecherry-Sierra Madre.
The SWCA Environmental Consultants ecologists contracted by PCW go out at night. They use powerful, handheld lights and binoculars to spot the birds by their eyes' reflection.
Keeping 50 birds fitted with thumb-sized, solar-powered GPS transmitters is a lot of work. Sage grouse rarely live longer than a year or two.
The $4,000 tracking devices often end up in the holes of scavenging rodents or up in the dinner-table-size nests of golden eagles.
"They feed a lot of other animals out here," explained Kehmeier.
Sage grouse seldom fly high enough to get hit by wind turbines. A bigger problem is they are thought to avoid tall objects, such as wind turbines, where predatory raptors might perch.
There is some potentially good news for energy developers: The sage grouse tracked at Chokecherry-Sierra Madre use no more than about 25 percent of the local landscape, according to the researchers.
But why? Nobody knows just yet.
The ecologists examine, weigh and photograph the sage grouse before fitting them with the tracking devices, which peg the birds' locations every couple of hours.
Data to date show sage grouse typically spend their days in low areas, where forbs and insects are plentiful. At night, they head to nearby ridges and hillsides to roost.
Sage grouse use the same mating and breeding areas, known as leks, year after year and follow predictable routes between patches of choice habitat, the research shows.
"They're literally following the green vegetation," Wojcik said.
In November, two females trapped and tagged in late September were on the move after lingering several weeks in one area. One had flown 10 miles.
The Chokecherry-Sierra Madre research will be first to document the condition of a sage grouse population both before and after wind farm development, said Chad LeBeau, an ecologist for Cheyenne-based firm Western Ecosystems Technology.
"The key component in their study is they have preconstruction data," LeBeau said.
LeBeau and others began a sage grouse study soon after the turbines went up at a different wind farm 60 miles away. They didn't notice sage grouse moving out but did note more deaths to predation.
The carcasses of other birds killed by the blades may have attracted predators such as badgers, or the blades may have distracted sage grouse from successfully evading predators, LeBeau theorized.
The Power Company of Wyoming plans to begin road work for Chokecherry-Sierra Madre next year. Turbines will start going up in 2017 if federal permitting goes smoothly.
Meanwhile, each spring and fall, often in horizontal snow, Kehmeier and Wojcik head into the rolling grass-and-sagebrush country night after night. Light reflected by jackrabbit eyes sometimes leads them on wild goose chases.
To date, they've tagged enough sage grouse to peg them at more than 500,000 locations.
"We're doing what we can to hopefully prevent a listing," said Miller. "We're using good science to inform our decisions."