Otero Mesa: The Last Desert Grassland

Otero Mesa is an ecologically important and visually stunning landscape located in southeastern New Mexico. Covering 1.2 million acres, it contains some of the largest remaining regions of Chihuahuan Desert grassland, providing habitats for a rich variety of plant and animal species, including species that are threatened, endangered, or in decline.

The Guadalupe Mountains, photo Steve Capra

Rising out of the grassy expanse, Otero Mesa’s scattered mountains are the site of world-class petroglyphs and other artifacts of Apache and other tribes that have inhabited the region, spanning thousands of years of cultural history.

Otero Mesa sits atop the Salt Basin aquifer, which despite its name is the largest untapped freshwater aquifer in New Mexico, estimated to contain 57 million acre feet of water, or 18 trillion gallons. The aquifer feeds several freshwater springs on Otero Mesa.

Today, Otero Mesa remains a relatively undeveloped wilderness, offering outstanding opportunities for camping, hiking, wildlife watching, and natural solitude. But the region is threatened by a renewed interest in oil and natural gas development, and it needs your help!

The landscape

Once widespread throughout the Southwest and Mexico, Chihuahuan Desert Grasslands are now among the most endangered ecosystems in North America. By the 1960’s, drought and over-grazing had transformed most of the grassland into dry desert scrub, in a process called desertification. Otero Mesa survived desertification because of a uniform layer of cement-like calcium carbonate, or calcrete, lying 2 feet beneath the surface, a depth which just happens to allow for grass to take root but not larger shrubs.

Alamo Mountain, photo Ken Stinnett

The grasslands of Otero Mesa are extraordinarily large, well-preserved, healthy and diverse, home to 13 species of grasses, including rare species not found elsewhere. Alamo Mountain, Flat Top Mountain, Wind Mountain, and the Cornudas Mountains rise out of the landscape. To the north, Otero Mesa is bounded by the Sacramento Mountains. To the east, Crow Flats and the Guadalupe Mountains. To the west, an escarpment drops into Tularosa Basin, and to the south the earth gradually descends into West Texas shrubland.


Otero Mesa is a window into the recent evolutionary past, still home to essentially the same assortment of plant and animal species that existed when Coronado rode through the region 500 years ago, looking for the Seven Cities of Gold.

Otero Mesa is home to 13 species of grass, mostly drought-resistant black grama and blue grama. Otero Mesa also hosts a high diversity of cactuses and wildflowers, includging  rare species like Guadalupe mescalbean, Guadalupe needlegrass, the gray sibara, the cliff nama, and five-flower rockdaisy.

Desert flora in full bloom, photos Lisa Mandelkern

The extremely rare coralroot orchid can be found in the Cornudas Mountains, in the southwest corner of Otero Mesa.

Otero Mesa supports 17 species of lizards and 13 species of snakes. Reptiles and amphibians include Texas horned lizards, gray banded kingsnakes, mottled rock rattlesnakes, box turtles, Couch’s spadefoot toads, and red-spotted toads.

The 2nd-fastest land mammal on Earth, the pronghorn antelope, which evolved alongside now-extinct American cheetahs, still roams Otero Mesa in the hundreds.

Pronghorn antelope, photo Joe Adair

Other native mammals include mule deer, javelin, kit foxes, coyotes, badgers, bobcats, mountain lions, bats, and black-tailed prairie dogs. The Cornudas Mountains provide an ideal reintroduction site for desert bighorn sheep.

As grasslands elsewhere have disappeared to desertification, Otero Mesa has become a refuge, particularly for grassland birds. Species that either breed or winter at Otero Mesa include horned larks, eastern meadowlarks, Cassin’s sparrows, common nighthawks, lesser nighthawks, lark sparrows, ferruginous hawks, scaled quails, grasshopper sparrows, chestnut collared longspurs, Brewer’s sparrows, Sprague’s pipits, and prairie falcons.

Nearly half of the grassland birds that rely on Otero Mesa are on a downward trend elsewhere. The major cause of this decline is habitat fragmentation.

The terrain and abundance of prey species in turn make Otero Mesa some of the best habitat for the endangered Northern Aplomado Falcon in the Southwest and serve as a reintroduction site for the endangered species. In recent years, several sightings have been reported. Photos Ken Stinnett

Historical and cultural sites

Archeological evidence in Otero Mesa reveals a rich cultural history dating at least back to the Archaic period (8,000 years ago), with some evidence of hunters as far back as 40,000 years ago, in the Pleistocene period. Remains of pit houses, rock shelters, and tool-stone quarries, along with tools and pottery, represent some of the earliest Paleo-Indian evidence in North America.

The Ancestral Mescalero Apache inhabited Otero Mesa on a seasonal basis as did the ancestors of the Tigua Tribe of Ysleta del Sur Pueblo. 


Standing on Otero Mesa, amidst a sea of yellow grass, with only the occasional ranch vehicle to break the silence, it can be hard to believe that the twin border cities of El Paso-Ciudad Juarez, with their millions of inhabitants, are only an hour’s drive away. The vast, uninterrupted vistas of Otero Mesa afford exceptional opportunities for recreation and escape from urban life.

In addition to big game hunting, Otero Mesa offers opportunities for non-consumptive uses of the land. Overnight camping is permitted on Otero Mesa, and the various mountain peaks make for great off-trail hiking. Wildlife watchers and birders will enjoy Otero Mesa’s biodiversity. And photographers will find endless inspiration in the expansive vistas and starry night skies.

Photo Ken Stinnett

Preserving undeveloped regions where people can go to find contemplative solitude is valuable. The grasslands and mountains of Otero Mesa that served as sacred sites for millennia now provide a source of spiritual reprieve and relief from the fast-paced, complex modern world.


Today, Otero Mesa is threatened. A renewed interest in oil and natural gas development stands to irreversibly damage this unique ecosystem, through seismic exploration, drilling, and road construction, even though the estimated energy returns would be minimal.

The natural gas below Otero Mesa is estimated to be enough to supply the United States natural gas consumption for only a few days to a couple of weeks, a tiny amount which would do little to nothing to increase energy independence or to lower fuel costs. However, the environmental costs of extracting the natural gas would be signification and irreversible.

Seismic exploration in Wyomming, photo Scott Groene

Oil and gas development involves clearing well pads and drilling wells, clearing corridors and constructing pipelines, laying cables, and constructing sumps for wastewater and other waste materials. Seismic exploration is used to map natural gas deposits; heavy vehicles drive off existing roads, detonating explosives to produce shock waves to detect what’s underneath the surface. This activity causes soil damage, erosion, and compaction, loss of grass species diversity, and the destruction of micro-topography which disrupts water run-off. It also disturbs wildlife movement and behaviors, causing stress, poor health, and declining population size. Even the dust generated from drilling and vehicle traffic would inhibit plant photosynthesis, reduce growth, and degrade habitats.

But the biggest threat development poses to Otero Mesa is the construction of roads and the resultant fragmentation of habitats. The BLM estimates that oil and gas development on Otero Mesa would lead to 350 new miles of road being built over 20 years.

Oil and gas development in the Permian Basin, photos SkyTruth

Habitat fragmentation is most important factor driving species loss worldwide, and the number one reason why so many grassland-dependent birds are in trouble today. For every mile of road, a nearly 1,000-acre zone of disturbance is created around it. If Otero Mesa is developed for oil and gas, bird populations could decline over 340,000 acres – a third of the total area. And as prey populations decline, this also threatens the region’s viability as a habitat for the endangered Aplomado Falcon.

Chihuahuan Desert grasslands are functional ecosystems, where every part is essential. Once they have been destroyed or damaged by human activities, like Humpty Dumpty, it is virtually impossible to put all the pieces back together again.

Otero Mesa is a uniquely valuable natural and cultural resource in need of protection. The Bureau of Land Management should put special provisions in place to protect Otero Mesa from oil and gas development.

Take action 


Want to experience the solitude and beauty of Otero Mesa for yourself? Click here for directions (from Las Cruces or El Paso).

More resources

Information on this page is drawn from the following reports. Click the links to view or download a PDF.

The Last Desert Grasslands: The Biological Case for Protecting Otero Mesa.
Walt Whitford, Ph.D., and Kevin Bixby
Southwest Environmental Center, 2006