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Rigged Game:

How Oil & Gas Drilling on Public Lands Threatens Habitat—and Hunting
by Dusty Horwitt, Chris Campbell and Sean Gray

Drill rigs are invading Western wildlife habitat and hunters are being squeezed out.

In just five Rocky Mountain states, Colorado, Montana, New Mexico, Utah and Wyoming, the federal government has currently leased almost 27 million acres of habitat for four key game species for oil and gas drilling. Drilling on these lands has doubled this decade with an average of 2,053 wells drilled per year between 2001 and 2006 compared to only 1,036 wells drilled per year between 1993 and 2000.

Wyoming saw the greatest increase in drilling on game habitat for the four species, antelope, elk, mule deer and sage grouse, with 884 wells drilled per year between 2001 and 2006, compared to 434 per year between 1993 and 2000. Overall, Wyoming now has the most oil and gas wells on game habitat with 34,808 wells drilled.

Many wells were drilled in crucial winter habitat that is critical to the survival of the species. In Colorado, for example, 139 wells were drilled per year on winter concentration areas between 2001 and 2006 compared to only 77 per year between 1993 and 2000. In Utah, there were 335 wells drilled per year on crucial winter habitat between 2001 and 2006 compared to 165 between 1993 and 2000. Drilling in crucial winter areas in Wyoming remained high, with 168 wells drilled per year between 2001 and 2006 compared to 162 between 1993 and 2000. (Drilling has impaired elk crucial winter habitat in Wyoming but drilling's effects on elk are mitigated by a winter feeding program).

Well drilling has doubled this decade in game habitats on federal land

Source: Environmental Working Group. Compiled from IHS U.S. Well Data.

This dramatic increase in drilling in game habitat was justified under the banner of energy independence. Yet drilling on these lands has produced a modest amount of energy, about seven percent of U.S. natural gas consumption over a 15-year period (1991-2005). Crucial winter habitats produced smaller amounts of energy: one percent of U.S. consumption in crucial winter habitat in Wyoming over the 15-year period and less than one half of one percent on crucial winter habitats in Colorado and Utah over the same time period.

At the same time, poorly planned drilling has steadily eroded the economic diversity of a region that increasingly depends on a variety of forms of outdoor recreation that all suffer when the landscape is degraded by thousands of oil and gas wells and the attendant roads, heavy truck traffic and noisy machinery, much of which operates 24 hours a day.

Alternatives such as energy efficiency and renewable energy can reduce the needless sacrifice of public lands. The American Council for an Energy Efficient Economy estimated that by 2020 the U.S. could be saving about the same amount of energy per year produced from the game habitats analyzed by EWG by implementing efficiency standards for several appliances not yet covered by federal rules (ACEEE 2001).

In addition, the West's growing emphasis on alternative energy from wind, solar and biomass can provide far more energy than can ever be extracted from beneath the migration corridors, fawning grounds and winter habitat wildlife needs to survive. In Colorado for example, the General Assembly has just approved a doubling of the amount of electricity that will come from alternatives by 2020 to 20 percent, underscoring the promise of clean, homegrown renewable energy.

In some areas, such as Wyoming's Pinedale Anticline, the increase in drilling has turned Western landscapes into industrial zones virtually overnight. In other areas, such as New Mexico's Carson National Forest near Navajo Lake, the recent spike in drilling has intensified impacts on areas already pockmarked with wells.

In Colorado, Montana, New Mexico, Utah and Wyoming — the states leading the West's natural gas boom — BLM has currently leased drilling rights on an estimated 23 million acres of mule deer habitat, 18 million acres of pronghorn antelope habitat, almost 17 million acres of sage grouse habitat and more than 13 million acres of elk habitat. Additional acres of habitat for the four species have been leased and drilled on state, private and Indian lands that are not included in this report.

For the latest installment in its Who Owns the West? series, EWG used mapping software to identify the locations where leasing and drilling have adversely affected habitat and hunting for the four important game species. Maps highlight local areas where hunters provide a first-hand account of how poorly planned oil and gas drilling is diminishing the quality of their hunts [Colorado, Montana, New Mexico, Wyoming]. The maps also show the increase in drilling over 10-year periods from 1967 to 2007.

EWG is releasing the report in collaboration with the National Wildlife Federation (NWF) and its affiliates in New Mexico, Montana and Wyoming. NWF has been a leading advocate for our public lands for over 70 years, and recently launched a campaign to mobilize hunters and anglers to protect public lands in the Rocky Mountain West including wildlife habitat threatened by energy development. NWF, whose mission is to inspire Americans to protect wildlife for our children's future, will feature EWG's report on its new website OurPublicLands.org.

Hunters, Anglers Increasingly Locked Out

In the last several years, hunters and anglers have expressed increasing concern that unchecked oil and gas development has threatened their access to federal land.

"The Bush administration has placed more emphasis on oil and gas than access rights for hunters," Ronald L. Schmeits, second vice president of the NRA, a member of its board of directors and a bank president in Raton, N.M. told the Washington Post earlier this year. "We find that our members are having a harder time finding access to public land (Harden 2007)."

"When President Theodore Roosevelt set aside the forest reserves that became the core of the National Forest System...he did so with the firm resolve that they be protected from excessive single uses," Rollin Sparrowe, board member of the Theodore Roosevelt Conservation Partnership wrote in testimony to the U.S. House of Representatives Natural Resources Committee. "What has occurred in less than a decade has been a freight train of rapid development that has assumed that getting access to gas and oil was first priority and maintaining access to quality outdoor experiences (like hunting and fishing)...are secondary (Sparrowe 2007)."

"Ongoing efforts to expedite energy development on public lands have turned traditional multiple-use management on its head by elevating oil and gas exploration to a dominant position," wrote Trout Unlimited in 2002. "As a result, gas and oil development is occurring at an unprecedented rate throughout the Rocky Mountain West, affecting tens of millions of acres, in some of the wildest places — with some of the best hunting and fishing — in the United States (TU 2002)."

Not only has the rush to drill impacted recreational opportunities, but it also threatens the livelihoods of outfitters who depend on hunting and fishing.

"When you start getting all these oil and gas wells on public land, you lose the people coming here," Western Colorado outfitter Keith Goddard told USA Today. "Will you pay me $2,500 to $3,500 to take you on a hunt when over here's a gas well and over there's a rig? How much do the people of Garfield County have to keep giving?" (Kenworthy 2004).

Hunters describe landscapes where they used to hunt with family and friends now covered with roads, well pads and waste pits. Mike Castinado said that he used to hunt with his father in a swath of New Mexico's Carson National Forest during the mid-to-late 1970s. On a return trip several years ago, he found the area nearly devoid of deer and scarred with extensive roads in a grid pattern more appropriate for New York City.

"It used to be a fairly pristine habitat at one time," he said. "There were a few isolated wells, but now they've got them in there pretty thick. When I was back there, I didn't see any other hunters. I think [they] came to the same conclusion I did: that it wasn't worth going there anymore."

Don Cuin, 63, describes a similar phenomenon in Wyoming's Red Desert. Cuin, a native of Rawlins, said that drilling has expanded significantly in the area in recent years, with bulldozers clearing the land by ripping out sage brush than can take 100 years to grow. Cuin believes that science should be used to drill responsibly, but that such considerations have been cast aside as the desert is consumed by a spreading network of wells, roads and pipelines.

"I have hunted antelope since my 13th birthday in what is referred to as the Red Desert," Cuin wrote in an e-mail. "I would have never dreamed we as Wyoming hunters would see the oilfield expand in the sheer vastness as well as the density we are now seeing...."

Impacts of Oil and Gas Drilling on Big Game

Though big game populations have expanded in at least some places in the West (sage grouse remain imperiled), Cuin has seen a decline in the mule deer herd in areas of intense drilling in the Red Desert. Scientific studies and government reports — some funded by the oil and gas industry — have substantiated his observations. These analyses have found negative impacts on wildlife due to drilling. Whether wildlife populations can endure and thrive as they are displaced from additional habitat is doubtful.

  • A 2006 study funded in part by Questar, a Salt Lake City-based company focusing on natural gas, found that mule deer in Wyoming's heavily-drilled Pinedale area were less likely to occupy areas closer to well pads than areas farther away. The study also found that such behavior appeared relatively quickly — within one year of development. After drilling, the deer tended to move from areas classified before development as highly likely to be used to areas classified as less likely to be used. This behavior suggested that the deer were moving to less suitable habitats. The researchers noted that the deer shifted their habitats even though drilling on federal land was restricted in the winter. The researchers did not note whether any of these restrictions were waived during the time of the study, allowing drilling to continue — a common practice on federal land in Wyoming (Sawyer et al. 2006).
  • A recent study by University of Montana professor Dave Naugle found a 50 percent decline in active sage grouse breeding grounds, known as "leks," inside oil and gas fields. The research also found that leks that remain active inside areas of oil and gas development shrink by half (Bleizeffer 2007).
  • The BLM's 2003 draft environmental impact statement for proposed gas wells in Utah's Uinta Basin found that mule deer and elk would face habitat fragmentation, loss of critical winter range and increased mortality due to collisions with vehicles among other hazards. The BLM noted that "displacement of big game (mule deer and elk) due to human activity has been documented by various studies" and reported that:
  • Depending upon the carrying capacity of the habitats and the number of animals involved, displacement would likely result in the reduced use of habitats near the disturbances and overcrowding of habitats into which the animals are displaced. This overcrowding may cause an increase in competition for space and forage, an increase in the animals' stress, and a decrease in the animals' physical conditions. Winter mortality may also increase and successful reproduction may decrease. The effects of displacement would be of greatest concern in the crucial and high value big game winter ranges.

The BLM explained that access to crucial winter habitat is especially important to mule deer (and likely for other species).

"A deer's ability to survive the winter and a doe's ability to produce viable offspring ultimately depend on fat reserves, which are continuously used during the winter. Increased stress that causes these fat reserves to be used more quickly, reduces survival for deer and reduces the intrauterine survival of fawns...The behavioral responses of mule deer to well and road development would include increased energy expenditures for avoidance of human activity and alterations of normal habitat use patterns (BLM Uinta Draft 2003)."

  • In a draft environmental impact statement for drilling in New Mexico's Otero Mesa, the BLM reported that "new road construction into previously unroaded or isolated areas could impact big game species significantly. Increased public access to these areas could result in increased legal take by hunters and higher levels of harassment, intentional (i.e. poaching) and accidental, to animals." (BLM Otero Draft 2000).

Energy Policy Encourages Poorly Planned Drilling

Federal agencies have directed field staffs to favor oil and gas drilling over other uses of federal land.

Early in his first term, President Bush issued an executive order stating that "for energy-related projects, agencies shall expedite their review of permits or take other actions as necessary to accelerate the completion of such projects" (Executive Order 13212, 2001).

In 2002, the BLM issued a memo to Utah land managers that read: "Utah needs to ensure that existing staff understand that when an oil and gas lease parcel or when an application for permission to drill comes in the door, that this work is their No. 1 priority" (BLM Utah Report 2002).

Other BLM staff members have stated publicly that the administration has a single-minded focus on energy that trumps BLM's authority to manage federal land for multiple uses. Steve Belinda, a wildlife biologist with BLM's Pinedale office, now with the Teddy Roosevelt Conservation Partnership, quit his job in 2006 because he said that he and other wildlife specialists were being required to spend almost all of their time on energy development (Harden 2006).

Drilling statistics reflect the administration's focus on oil and gas. In 2004, the BLM approved a record 6,130 applications for drilling on public lands, up from 3,810 the previous year. In 2005 it broke its own record with 7,736 approvals (BLM AFMSS 2004, Foster 2005, Clarke 2006).


EWG consulted data from fish and game departments in Colorado (CDW 2007), Montana (MFWP 2007), New Mexico (NMDGF 2007), Utah (UDWR 2007) and Wyoming (WGF 2007) to plot the location of habitat on federal land for antelope, elk and mule deer including winter range and, in most states, crucial winter range. EWG used data from The Mule Deer Project to plot overall mule deer range (Mule Deer 2007). EWG accessed data from the U.S. Geological Survey to plot the location of sage grouse habitat on federal land (USGS Sage 2007).

EWG plotted the location of wells using government and industry data from IHS Energy, a private firm based in Englewood, Colorado (IHS 2007). EWG obtained production data through a Freedom of Information Act request to the U.S. Department of the Interior's Minerals Management Service (MMS 2007). EWG accessed leasing data from BLM's Legacy Rehost 2000 database to plot the location of current leases on federal land (BLM LR 2000).

* Research assistance by Trina Chiasson.


American Council for an Energy Efficient Economy (ACEEE). 2001. Opportunities for New Appliance and Equipment Efficiency Standards: Energy And Economic Savings Beyond Current Standards Programs.

Bleizeffer, Dustin (Bleizeffer). 2007. Working Around the Grouse. Casper Star-Tribune. April 27, 2007.

Bureau of Land Management (BLM Utah Report). 2002. Oil and Gas Program Review Final Report, conducted August 13-17, 2001, issued January 4, 2002.

Bureau of Land Management (BLM Uinta Draft). 2003. Resource Development Group Uinta Basin Natural Gas Project, Draft Environmental Impact Statement. July 2003 at 76, 159, 162.

Bureau of Land Management (BLM Otero Draft). 2000. Draft RMPA/ElS for Federal Fluid Minerals Leasing and Development in Sierra and Otero Counties 4-29. Accessed online January 10, 2005 at http://www.nm.blm.gov/lcfo/white_sands_rmpa_eis/white_sands_rmpa_eis.html.

Bureau of Land Management, U.S. Department of the Interior (LR 2000). 2007. Legacy Rehost 2000, January 2007 download.

Clarke, Kathleen (Clarke). 2006. Hearing of the U.S. Senate Committee on Senate Energy and Natural Resources (Statement of Kathleen Clarke Director, Bureau of Land Management Director). June 27, 2006.

Colorado Division of Wildlife (CDW). 2007. NDIS Data. Accessed February 26, 2007 at http://ndis.nrel.colostate.edu/ftp/ftp_response.asp http://ndis.nrel.colostate.edu/ftp/ftp_response.asp.

Executive Order 13212 of May 18, 2001. 2001. Actions To Expedite Energy-Related Projects. Accessed online June 18, 2001 at http://www.archives.gov/federal_register /executive_orders/2001_wbush.html.

Foster Natural Gas Report (Foster). 2005. Senate Energy Committee's Natural Gas Conference Mulled a Plethora of Issues and Recommendations to Protect, Develop and Underwrite Natural Gas Resources in the U.S. and from Abroad. January 27, 2005.

Harden, Blaine (Harden). 2007. NRA Pressured To Resist Bush Energy Policies; Hunters Wary of Limited Land Access. The Washington Post. January 7, 2007, at A3.

Harden, Blaine (Harden). 2006. Neglected Vows Cited At BLM; Agency Was to Monitor Impact of Wyo. Drilling. The Washington Post. September 1, 2006, at A3.

IHS Energy (IHS). 2007. Rocky Mountain well data. January 1, 2007.

Mule Deer Project, The (Mule Deer). 2007. Accessed online 2007 at http://www.gis.usu.edu/current_proj/muledeer.html.

Minerals Management Service, U.S. Department of the Interior (MMS). 2007. Onshore oil and gas production data from Oil and Gas Operations Reports (OGOR). January 2007.

Montana Fish, Wildlife, and Parks (MFWP). 2007. GIS Layers. Accessed online February 27, 2007 at http://fwp.mt.gov/insidefwp/GIS/download.aspx#Wil.

New Mexico Department of Game and Fish (NMDGF). 2007. Electronic mail attachment from Lance Tyson received March 7, 2007.

Sawyer, Hal et al (Sawyer). 2006. Winter Habitat Selection of Mule Deer Before and During Development of a Natural Gas Field. The Journal of Wildlife Management, 70 (2), 396-403 (2006).

Sparrowe, Rollin D. (Sparrowe). 2007. Access Denied: The Growing Conflict Between Fishing, Hunting and Energy Development on Federal Lands: Full Committee Oversight Hearing before the U.S. House of Representatives Committee on Natural Resources, 110th Cong. (March 27, 2007) (statement of Rollin D. Sparrowe, board member, Teddy Roosevelt Conservation Partnership).

Stipulation and Joint Motion to Enter Order Approving Settlement and to Dismiss the Third Amended and Supplemented Complaint (Utah Settlement). 2003. U.S. District Court, District of Utah, Central Division, April 11, 2003.

The Wilderness Society.

U.S. Geological Survey (USGS). 2007. Sagemap. Accessed online April 10, 2007 at http://sagemap.wr.usgs.gov/.

Utah Division of Wildlife Resources (UDWR). 2007. Index of Available GIS Data. Accessed February 26, 2007 at http://dwrcdc.nr.utah.gov/ucdc/DownloadGIS/disclaim.htm.

Wyoming Game and Fish (WYGF). 2007. Big Game GIS Data. Accessed online February 27, 2006 at ftp://gf.state.wy.us.


The Environmental Working Group would like to thank the dedicated foundations whose support made this project possible: The William & Flora Hewlett Foundation and the Rockefeller Family Fund. The opinions expressed in this analysis are those of the authors and do not necessarily reflect the views of the supporters listed above. EWG is responsible for any errors of fact or interpretation contained in this analysis.