Putting the Squeeze on Pronghorn

How federal plans to drill thousands of gas wells in Wyoming threaten the largest mammal migration in the Lower 48

  • Brian Maffly
  • Apr 01, 2004

AS SNOW COVER FADES from southwestern Wyoming’s panorama of plains, buttes and dunes, thousands of pronghorn move north across the Red Desert and the Green River Basin to the Gros Ventre Mountains and as far as Grand Teton National Park, a migratory route that can extend almost 170 miles. Among them mingle thousands of mule deer, and together the two species make up the largest migratory movement of any land mammals in North America south of the Canadian border, a living remnant of the ancient Pleistocene.

Pronghorn numbers stand at about 1 million in the United States and Canada, almost half of the animals in Wyoming. But even in Wyoming’s prime habitat, the species is beset with threats that have reduced the herd about 40 percent since 1984. “We’ve cut the West into tiny pieces, and pronghorn are big-landscape creatures,” says Steve Torbit, director of NWF’s Rocky Mountain Natural Resource Center in Colorado. “It’s a classic case of death by a thousand cuts.”

When Fences Kill

One of the deepest cuts is fencing, which ranchers began putting across the plains late in the 19th century. Although pronghorn seldom jump fences, they can duck under certain types—the Wyoming Game and Fish Department recommends fences with an unbarbed bottom strand at least 16 inches above the ground—but few fences are put up to accommodate pronghorn. Mesh fences anchored to the ground cut off the animal’s movement.

A barrier of a different sort came to Wyoming nearly 40 years ago in the form of Interstate 80. Fences that parallel the highway have cut the pronghorn population into northern and southern herds, with little or no genetic sharing between them, says Bill Rudd, wildlife management coordinator for the Wyoming Game and Fish Department.

Many secondary roads also block pronghorn movement. “Pronghorn can squirt through along creeks but not at fences or underpasses,” Rudd says. In effect, Wyoming pronghorn habitat is becoming a checkerboard that fragments the species into increasingly isolated groups.

As pronghorn numbers have declined because of factors such as fencing, highways and drought, the state Game and Fish Department has cut back deeply on pronghorn hunting, which raises revenue for wildlife management. This loss of funds has in turn caused reductions in pronghorn research for most of the past 20 years.

Such data are becoming ever more crucial as natural gas development burgeons in the Green River Basin and the Red Desert. Two miles under the sagebrush of southwest Wyoming lies a sea of natural gas that exceeds 300 trillion cubic feet, enough to fuel the nation’s current rate of consumption for 14 years. According to a recent estimate by the federal Energy Information Agency, U.S. natural gas use will rise 60 percent by 2020. With production declining nearly everywhere else in the Lower 48, public land in the Rocky Mountain states will be expected to feed the demand. At risk is the ecological health of the river basin and the Red Desert as well as the 100,000 or so pronghorn that spend part or all of the year there.

Those pronghorn could be traded off for less than the promised 14 years of natural gas. “Most of the gas estimated to exist in the Green River Basin is not recoverable using current technology,” says Kate Zimmerman, an NWF land stewardship policy specialist in Colorado. “So the trade-off today—and for the foreseeable future—is not between saving some pronghorn or extracting 14 years of energy. It is between extracting the small portion of energy that can be recovered now or preserving the long-term viability of Wyoming pronghorn habitat. The natural gas in the ground will not be wasted if we take our time and figure out how to get it out without devastating the surface.”

Dangerous Moves

One of the key threats that natural gas development poses to pronghorn centers on the narrowest portions of migration routes. The Upper Green is dotted with such bottlenecks, but only recently has their importance become known. “You lose one of these bottlenecks, you lose the whole migration corridor,” says Hall Sawyer, a Laramie biologist who has been mapping pronghorn and deer movements for the past three years.

The most famous bottleneck, Trappers Point, is a few miles west of Pinedale, Wyoming, where the terrain undulates to a high point between the Green and New Fork Rivers. Twice yearly the topography funnels several thousand migrating pronghorn through a mile-wide slot between the rivers—a bottleneck that has been effectively narrowed to just a half mile by houses, dirt roads, fences, a livestock holding pen and U.S. Highway 191.

Despite the importance of Trappers Point to pronghorn, the area’s primary landlord—the federal Bureau of Land Management (BLM)—in 2002 quietly offered 2,300 nearby acres to private companies for gas drilling. A local conservationist uncovered the plan and notified state wildlife officials, who sent a letter to BLM urging the agency to yank the offered lease. “We view those bottlenecks as at risk,” says Pinedale Game and Fish supervisor Bernard Holz. “It wouldn’t be a good decision to put anything in that corridor.”

BLM officials agreed, but too late to stop the auction. When BLM subsequently announced that the lease could not go forward, the high bidder, an Oklahoma energy firm, appealed in court. The dispute still is not settled.

Two months before that fiasco, BLM auctioned another Trappers Point-area lease, prompting a letter of protest from residents. One protester was Gordon Johnston, chairman of the usually pro-development Sublette County Commission. “There was no thought in there for antelope and the migration route in that area,” says Johnston, who lives just west of Trappers Point.

Johnston’s county has ridden the most recent gas boom to prosperity: Sublette is one of the West’s leading natural gas producers, behind only New Mexico’s San Juan County. Benefits include good-paying jobs, low unemployment and industry tax payments that cover nearly half the total county budget. With such financial props on the side of industry, rallying support for pronghorn is a challenge.

Among Johnston’s supporters is the publisher of the local newspaper, the Pinedale Roundup. “Sublette County has a rich and proud heritage of oil and gas development,” wrote Rob Shaul, a fifth-generation local, in a recent editorial. “But today, we’re taking a stand against the future development of oil and gas on [federal] lands in Sublette County.”

Shaul, Johnston and their allies face powerful foes, including a Congress that favors fast-track oil and gas extraction and a presidential administration that has issued directives ordering BLM staff to “expedite their review of permits or take other actions as necessary to accelerate” energy development. BLM has already leased about a million acres in the Green River Basin and is under administration orders to start drilling as quickly as possible.

Commenting on her agency’s new high-speed approach to energy development, BLM director Kathleen Clarke said it would be “a much-improved method of working with our energy partners [in industry].” Last summer, Alan Rabinoff, BLM deputy state director for minerals and land, said that in Wyoming, “We are expediting the process, not cutting corners. When I say expediting, I mean looking for ways to be more efficient.”

And yet, a lot of BLM professionals are worried, says Mike Chiropolos, an attorney with Western Resource Advocates in Denver. “We’ve still got some dedicated people out there in the agencies. And they know, if they have to focus all their efforts on sucking minerals out of the ground, they won’t be able to meet their other obligations,” such as the panoply of laws requiring multiple-use management, protection of species and so on.

Under the accelerated plan, an area of the Red Desert called the Jack Morrow Hills, prime pronghorn habitat, is slated for 5,000 natural gas wells to be sunk on 75 percent of the hills. Meanwhile, BLM has rejected protecting more than 100,000 acres of potential wilderness in the area. “Wyoming is the best pronghorn habitat in the nation,” says Rudd, “but we are cutting the heart out of it.”

Even state elected officials are being ignored under the White House plan to expedite energy development. When Wyoming governor Dave Freudenthal toured the Jack Morrow Hills last summer, he told BLM that development there could be “disastrous” for wildlife. He prefers to see more land purchases or exchanges to keep some sensitive areas from development. “In the current political climate, such sensible solutions seem unlikely to get a fair hearing,” says NWF’s Torbit.

Wildlife Left Out

Energy development is supposed to follow federal guidelines designed to protect wildlife, such as a ban on drilling in crucial pronghorn and deer winter range from November 15 to March 15 and limitations on how closely companies can drill to plover, raptor and sage grouse nesting sites. “We have never said that the industry should stay out of Wyoming,” Torbit says. “Our concern is a matter of when, where and how they do their work. Some areas should be off limits for a time, and mitigation and rehabilitation should be part of the performance requirements for gas. As it is now, no accommodations are being made for wildlife.”

Instead, BLM has given energy companies generous exemptions to the guidelines. In the most glaring example, with no specific public comment process or formal environmental analysis, BLM recently gave Salt Lake City-based Questar permission to drill in crucial mule deer range for an entire winter.

Last August, BLM headquarters ordered field offices in the Rockies region to apply only the “least restrictive” wildlife protections and to put more emphasis on waivers and exemptions with the intention of “reducing or eliminating impediments to oil and gas leasing.” BLM will even let oil and gas companies take over assessment of possible impacts on wildlife, with BLM providing only oversight. Meanwhile, due to a lack of state funds, biologists can monitor neither pronghorn population trends nor habitat loss resulting from oil and gas development, Rudd says. No hard data have even been gathered on how oil development affects the pronghorn.

So far, Rudd says, state authorities have been unable to work out agreements under which developers will mitigate the loss of pronghorn habitat. In fact, BLM is adjusting its “reasonably foreseeable development” for the Green River Basin upward, from 5,120 new wells over the next 17 years to as many as 10,000. “For now,” says Torbit, “the pronghorn are facing one of the worst threats in the past century. Through well-planned mitigation and restoration we could have both pronghorn and energy, but not the way things are going. The pronghorn survived the Pleistocene, they survived market hunting, they even survived Interstate 80, but they may not survive this administration.”

Brian Maffly writes from Bozeman, Monana. High Country News Editor in the Field Ray Ring contributed to this story, which is adapted from an article that first appeared in High Country News. To see the original text, go to www.hcn.org.

America's Unguarded Desert Gem

The 8-million-acre Red Desert remains the largest unprotected and undeveloped high-elevation desert in the United States. For more than a century, efforts to win permanent protection have failed. The push began in 1898, when Frank Dunham, a sport hunter from Lander, Wyoming, tried to get the area designated as a winter game preserve. Wyoming governor Leslie Miller tried again in 1935, seeking to turn the area into Great Divide Basin National Park. In 1968, a local rancher, Tom Bell, failed to win support for protecting the area as a North American antelope range. Attempts to make the Red Desert into a wild horse refuge, a national wildlife refuge, a national monument and a national natural landscape have all run aground. In fact, a 1950 amendment to the federal Antiquities Act, which allows the president of the United States to create national monuments by executive order, made Wyoming the only state in which the president cannot take such action. However, the president does have the authority to open unique places in the state, including the Red Desert, to the oil and gas industry.

NWF TAKES ACTION: Saving Wyoming's Pronghorn 

NWF work on behalf of Wyoming pronghorn dates back to 1983, when the organization began fighting a rancher who had put up 28 miles of 5-foot-high woven fence in crucial pronghorn winter habitat, locking the animals out of his own land as well as 100,000 acres of Bureau of Land Management (BLM) land. Thousands of migrating pronghorn died as they crowded against the fences during the next two winters, until an NWF lawsuit ended in removal of the fence. Today, NWF is focusing on energy development in the Red Desert and the Green River Basin. BLM is revising its management plans for nearly all of the Red Desert, deciding if lands will be protected for wildlife and where and how oil and gas development will be authorized. NWF, with other conservation organizations, submitted comprehensive proposals for management of these lands. NWF also is fighting to preserve crucial wildlife habitat by tracking BLM’s proposal to develop more than 3,800 coalbed methane wells on the 250,000-acre Atlantic Rim portion of the Red Desert. For more information, go to www.nwf.org/reddesert.

Pronghorn: High Plains Sprinter 
Scientific Name: Antilocapra americana

Population: About 1 million in the United States and Canada

Habitat: Western grasslands from Canada south into Mexico

What’s in a name? Pronghorn, found only in North America, are not antelope at all but are closely related to goats.

Fleet of foot: Pronghorn can sustain a speed up to 60 miles per hour, an adaptation they developed millennia ago to evade a now-extinct North American cheetah.

The hunt is on: Prior to European settlement of North America, pronghorn numbers likely exceeded 30 million. By the middle of the 19th century, pronghorn were among the species killed for sale in meat markets. During the winter of 1868–9, some 2 million pronghorn gathered between Denver and Cheyenne, forming a herd 10 to 12 miles long and up to 200 yards wide. So densely packed that they changed the color of the countryside, they were killed by the wagonload and sold for 6 cents apiece in Denver.

Steep decline: Wholesale slaughter and habitat loss reduced the pronghorn to no more than 15,000 by 1915, but intensive conservation efforts have helped them recover.

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Where Have All the Pronghorn Gone?The pronghorn has shrugged off some powerful adversaries in the past. It survived the era of saber-toothed cats, cave bears and dire wolves. An old enemy, a North American cheetahlike species, died off while the pronghorn continued racing across the plains. Glaciers came, and glaciers went, but the pronghorn kept on ticking. Once the fleet-footed animal shared grasslands with woolly mammoths and rhinos, but those behemoths disappeared. Yet the pronghorn was fruitful and multiplied: By the time Lewis and Clark came drifting across the Great American Desert, the pronghorn may have numbered around 60 million.

But not for much longer. Ernest Hemingway once said that continents age quickly once we come to them, and in the 19th century we came to the Great Plains. Lewis and Clark introduced the world to pronghorns, referring to them as goats or antelope when they encountered the animals around early September 1804 near what is today Greenwood, North Dakota. In honor of that first meeting, they shot and killed one of the pronghorn.

Shooting pronghorn was a not unheard of tradition in the American West, dating back to at least 1540, when a hunt was held in the Mexican state of Hidalgo in honor of a local viceroy. Participants killed 600 deer as well as a number of deerlike creatures, unknown in Spain, that the hunters said not only ran but flew. Presumably, pronghorn.

Except for such isolated hunts, the pronghorn drew little attention until after the War Between the States, which ended in 1865 and freed up soldiers and settlers for the West, and the haunts of the pronghorn and bison.

Like the bison, the pronghorn was about to meet its match in the game of survival. Hunting was unregulated in the 1860s and 1870s, and bullets aimed at pronghorn flew without restraint. The animals were easy to find. Naturalist George Bird Grinnell, who traveled with Lieutenant Colonel George Custer during a western expedition, reported that the troops were surrounded by pronghorn day after day. Near North Park, Colorado, he saw so many that they seemed to cover the land. The Ute Indians held a circle hunt in the area in 1868 and killed 4,400 of them. Miners shot them for food. Professional hunters shipped pronghorn meat to eastern markets.

The killing occurred on a massive scale. For example, during winter 1868-69, a passenger on the newly opened railroad that ran between Denver and Cheyenne would have seen 2 million pronghorn gathered in the foothills overlooking the track, a single herd 10 to 12 miles long and 200 yards wide. Wagonloads of these animals were killed throughout the winter, and the carcasses sold for six cents each.

The pronghorn outlasted the bison by some 20 years. Even in the 1890s, the pronghorn still could be found in herds of hundreds. But shooting, combined with habitat loss to farming and ranching, doomed the species. In Yellowstone National Park, hunters killed thousands yearly from 1872 to 1883, until the hunting was brought to a halt in 1894. In 1913, only 500 pronghorn survived in Yellowstone.

The species was dwindling everywhere. In Colorado, the pronghorn population fell from a meager 25,000 in 1898 to only 2,000 a decade later. No wonder that, in his 1913 book Our Vanishing Wildlife, New York Zoological Society director William T. Hornaday predicted, "The prong-horned antelope, unique and wonderful, will be one of the first species of North American game to become totally extinct. We may see this come to pass within twenty years."

As he wrote that, the Wool-Growers Association in Montana, a sheepman advocacy group, was hiring a Washington lobbyist to stop a congressional proposal to set aside 15 square miles of prairie around Snow Creek, Montana, as a national pronghorn preserve.

But the tide was turning in favor of the pronghorn, and in just the nick of time. Ranchers, faced with widespread damage to grasslands from overgrazing by livestock, reduced the number of cattle they put on the prairies, particularly as fencing and private landholding became the norm. Pioneer farmers, discovering that the prairies they plowed were too dry for crops, abandoned the more arid parts of the plains. Suddenly, the pronghorn breadbasket with starting to refill.

Equally important, various state wildlife agencies began reintroduction programs to restore the pronghorn. Trapping the animals in the few areas where they were still abundant and releasing them in vacated habitat, western states began reviving the lost herds. Today, about a million pronghorn roam the West—only a fraction of the number that once awed Lewis and Clark, but still a vast improvement over the small, isolated bands to which 19th century excesses had reduced the pronghorn.

Now, as National Wildlife makes clear, new challenges confront the pronghorn in Wyoming and other parks of the West as energy development converts open grasslands into fields of wells and drilling rigs riven by roads. The future for the pronghorn depends on whether we take as our management models the excessive approach of the 19th century or the more diligent measures of the state agencies that helped recover the pronghorn by use of science and hard work.—Roger Di Silvestro

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