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Walk along the quiet roadside eight miles north of Marathon, where your only noticeable company might be a lonely passing car or golden eagle, and you’ll probably set off an alarm system. The sprawling high-desert grassland there is pocked and cratered with dirt mounds, out of which, like tiny periscopes, peer the eyes of black-tailed prairie dogs. When one of these sentinels spots you—and decides you’re a predator—he’ll begin squeaking, shrill and steady like a car alarm. Soon, other nearby watchmen will join the distress chorus.

Observe these grassland denizens awhile longer, and you might witness another display, referred to by some as “the jump-yip.” A prairie dog resting on his chunky haunches lifts his tawny breadloaf-sized body up into the air, flings his stubby arms wide, and lets out a mighty “weeoh!” The melodiously urgent sound could easily be mistaken for a bird call, and like a bird call, it elicits an immediate response. When one prairie dog jump-yips, it triggers a wave of jump-yipping among nearby prairie dogs. The group of yelping rodents resembles a hyped-up lilliputian soccer team doing a victory dance.

These calls are among the dozen or so vocal signals that prairie dogs have at their command, ranging from their namesake dog-like barks, to chuckles, purrs and snarls. Combining these sounds with the use of scent and touch—including a “kiss” to distinguish friend from foe—prairie dogs have a remarkable system of communication. For example, Northern Arizona University biologist Con Slobodchikoff has found that Gunnison’s prairie dogs, which live elsewhere in the Southwest, can actually use their calls to describe the size, color, speed and specific type of approaching predators.

This complex chatter is only one aspect of prairie dog society’s sophistication. Their colonial way of life, cooperative vigilance, and labyrinthine towns maximize their ability to detect and avoid predators. Prairie dog burrows, which often stretch for miles, are elaborately designed with escape tunnels and separate chambers for rearing pups, sleeping, listening for above-ground alarm calls, and latrines, explains John Karges, the Nature Conservancy’s West Texas program manager. Prairie dog towns even have ventilation systems: the height and placement of burrow entrances is varied such that swift prairie breezes are pulled underground through a burrow’s many tunnels, Karges says. The crater-like shape of these mounded-dirt entrances also keeps out harsh rains and provides a watchtower for observing trespassers. By nibbling down any tall grass or shrub seedlings around their watchtowers, prairie dogs keep their view clear and deprive potential predators of a vegetal hunting blind.

Despite prairie dogs’ many defenses, their subterranean civilizations have been greatly diminished in West Texas and elsewhere in their native range, which extends from far northern Mexico, across the Great Plains, into southernmost Canada. In the 1800s, the ground beneath this vast swathe of North America teemed with a purported five billion prairie dogs. In Texas alone, a turn-of-the-century state biological survey roughly estimated there were as many as 800 million Texan prairie dogs, whose colonies covered more than 57 million acres. Our state was also once home to the largest known colony; the town allegedly stretched from Amarillo to Abilene and was probably home to 400 million black-tailed prairie dogs, according to prairie-dog expert John Hoogland’s book, The Black-Tailed Prairie Dog: Social Life of a Burrowing Mammal.

But prairie dog populations have been decimated by a century of disease, habitat destruction, hunting and eradication programs. They’re now thought to occupy less than one percent of their native range, with Texas’ towns covering less than 150,000 acres, according to a Texas Parks and Wildlife Department publication. They’ve bounced back over the past few decades, but some species are still endangered or threatened. A few years ago there was a failed effort to get federal protection for black-tailed prairie dogs— Texas’ native species and the most commonly seen in zoos.

While there are still a number of healthy colonies in our region, many prairie dogs have been lost from here as well. Historically about 13 percent of Texas’ black-tailed prairie dogs lived in grasslands west of the Pecos, including parts of Jeff Davis County, northern Brewster County and puportedly Presidio County, where their past presence has not been confirmed. But a recent census revealed only three percent of the state’s total population remain in the Trans-Pecos, says John Young, a state parks department mammalogist.

The decline of prairie dogs is an ecological misfortune, and even more unfortunate is that their eradication has been based on largely discredited notions. For the past century, prairie dogs have been regarded by many landowners as pests who compete with livestock for food and dig noisome holes that trip and break the legs of horses and cattle.

Because of these concerns, a program of poisoning, drowning and shooting prairie dogs brought them dangerously close to extinction by the early 1970s, according to Hoogland’s book. Prairie dog antagonism persists today and not totally without cause. Young points out that prairie dogs are still a nuisance when they settle under a golf course, airport or cemetery, where they’ve been known to excavate bones. And particularly if natural predators are absent, prairie dogs can overgraze an area leaving nothing but bare earth, says Bonnie Warnock, a Sul Ross State University natural resource management professor.

“They’re not appropriate everywhere,” Warnock says. “I think the key to it is management. If they start increasing into an area where they’re not wanted, it’s very easy to control their population through hunting or poisoning.”

But as grass-gobbling, leg-breaking villains, prairie dogs have been vindicated by decades of research, and they’re now understood to be integral members of grassland ecosystems. Confirmed reports of broken legs are rare if non-existent, and competition with livestock has been shown to be minimal, Hoogland writes, adding that prehistoric prairie dog towns co-existed with large herds of grazing American bison.

“I grew up with prairie dogs, so I always saw them as a source of income,” says Warnock, who was raised on a Brewster County ranch. “The cattle would graze a lot of times preferentially in the prairie dog town because it would green up faster.”

Prairie dogs, she explains, are among the important creatures known as a keystone species. Between 140 to 300 other species are thought to rely, directly or indirectly, on prairie dogs. They’re food for several birds and mammals, including ferruginous hawks, golden eagles, foxes and badgers. And their burrows provide shelter for many other critters, from burrowing owls to myriad reptiles and insects.

Perhaps one of the best examples of a prairie-dog dependent is the black-footed ferret, whose life revolves around eating the rodents and tunneling through their burrows. As prairie dog numbers have dwindled, these ferrets have likewise faced a precipitous decline into near extinction. Gone from our area, they remain one of the country’s most endangered animals.

Grassland ecosystems benefit from prairie dogs in other ways, Warnock explains. Their digging improves the soil, and their herbivorous habits encourage the healthy growth of short and tall grasses, a mix that’s needed by some grassland birds whose populations are declining. Studies have also shown that prairie dog-mowed grass, though more sparse, is more nutritious than grasses outside their towns, according to Hoogland’s book. Warnock is now looking into studying whether reintroducing prairie dogs can actually help restore range grasslands, and, in particular, if prairie dog foraging could help control the spread of unwanted shrubs, as has been suggested by a recent study in north Texas.

Back at the colony outside Marathon, after the jump-yipping subsides, the prairie dogs graze the short-cropped grass around their burrow mounds, while cattle graze in the distance. Something stirs suddenly in a patch of taller grass, and the prairie dog alarm system goes off again. While some people might think differently, for a hundred or so other grassland residents, what they’re protecting is well worth the vigilance.

Urban prairie dogs are often in need of relocation, and landowners interested in letting relocated prairie dogs settle on their property may contact John Young at (512) 389-8047. Texas Parks and Wildlife also has a volunteer prairie dog monitoring program; for information call (800) 792-1112 ext. 8062.

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