Places We Protect

Marathon Grasslands Preserve


An open expanse of sweeping brown grasslands swaying in the wind and low mountains.
Marathon Grasslands This preserve protects desert grassland habitat in West Texas' Marathon Basin. © Jerod Foster

This expansive desert grassland is nestled in the arid West Texas landscape.



Far West Texas offers iconic panoramas, filled with vast swaths of rugged desert topography accented with muted scrub brush, cactus flowers and rocky plateaus that seem to rise from the terrain like a mirage. Tucked into a section of this weathered arid landscape, at the heart of the Trans-Pecos, is a pocket of expansive grassland that now includes The Nature Conservancy’s (TNC) Marathon Grasslands Preserve.

The 2,701-acre preserve in the northern part of the Marathon Basin region represents some of the most diverse Chihuahuan Desert grassland habitat in Texas and supports a wide array of wildlife.




2,701 acres

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An open field of tall grass with red and white flowers.
Amongst the Mountains TNC's Marathon Grasslands Preserve is comprised of diverse grasslands that extend up to the Glass Mountains. © Jerod Foster

Why This Place Matters

Here, sweeping grasslands extend up to the Glass Mountains, sheltering wildlife that includes migratory raptors and grassland birds, far-ranging pronghorn antelope, kit foxes, burrowing owls and golden eagles. The preserve also provides habitat for the federally endangered northern aplomado falcon. Most often seen in pairs, northern aplomados have steel grey backs, red breasts, a black “slash” mark across the belly and striking black head markings.

Marathon Grasslands Preserve also harbors a portion of the largest black-tailed prairie dog town in the Trans-Pecos region of Texas. Scientists refer to prairie dogs as the architects of North America’s grasslands—and they are vital to maintaining the diversity in the Chihuahuan Desert. These herbivorous animals gnaw off woody shrubs, like mesquite, that would otherwise overtake the grassland habitat. They are also excavators; colonial prairie dogs burrow as much as 10 feet below ground to build their elaborate dens, breaking up hard-baked desert soil in the process, which makes for more fertile grasslands and better foraging. Though prairie dogs are critical to maintaining the integrity of grassland landscapes, habitat loss and fragmentation, along with human intolerance, have led to declining populations.

Photos from Marathon Grasslands Preserve

Discover the diverse plant life and wildlife at this desert grassland preserve.

A large bird with a sand colored body and outstretched mottled brown wings and tail feathers.
A rainbow forms during a storm in the desert.
Puddles pool over brown grasslands and shrubs with mountains at the edge of the field in the background.
Two small burrowing owls sit together on the rocky desert ground.
Virga falls from dark clouds over a gravel road etched through tall grass.
A plump prairie dog sits at attention on top of a dirt mound.
A bush with sharp spines grows above a desert grassland field.
Mountains tower at the edge of a field will with brown, green and yellow grass.
A cabin is lit up with red lights as evening turns to night in the desert.
A turtle with yellow and dark brown markings on its sandy shell.
A deer runs across a field of grass.
People and nature thrive TNC has been working with local landowners to install pronghorn-friendly fencing throughout the preserve. © Jerod Foster

What TNC Is Doing

TNC's work at Marathon Grasslands Preserve highlights conservation-friendly ranching techniques and sustainable land management practices, complementing more than two decades of conservation work in the Davis Mountains and Marfa grasslands. This iconic region faces myriad threats, including the cumulative effects of drought and climate change and the suppression of a natural fire regime. But with the cooperation of regional landowners, partners and researchers, we are working to protect the heritage wildlands of the Trans-Pecos region.


  • Marathon Grasslands Preserve is closed to the public but occasionally opens on select dates for guided preserve tours. Check the Marathon Grasslands Preserve Tours Page for the latest tour schedule. For more information, contact  West Texas Education and Outreach Coordinator Kaylee French (

  • View a map of TNC's protected properties and preserves in West Texas, including Marathon Grasslands Preserve.