United States. National Park Service , Devils Tower National Monument, Wyoming (1984)

“ Hugging the steep upper slopes of the Tower’s circular base, the trail allows a speedy orbit. The falcon continues to scream. Now along the southeastern face, I can hear the climbers shout to one another. The belly of the cloud is overhead and angry-black. Lightning flashes are now immediately followed by loud reports, sharp as splitting wood. I should turn back 42 and drop to the nearby trail that returns to the campground, but the swell of wind in the pines and the occasional crash of falling snags is invigorating. A sudden invasion of cold air means the rain will come heavy and soon. ”

“ All around me are boundaries—conspicuous where defined by plants, but invisible where respected by animals. No prairie dog has ever traveled across this slope, and no red squirrel has ever scurried into the treeless expanse of the prairie dog town. On no occasion would a rock wren enter the deep pine forest. Should its food supply somehow vanish, it would perish among the bare earth and gully washes of its own habitat rather than hunt the dog town or forest floor.
Each animal species is adapted to the conditions of its preferred environment. ”

“ Some animals indigenous to the Great Plains find a protected home in Devils Tower National Monument. Gone from this area are the bison that once roamed the prairie grasslands in great numbers, and the fastest plains animal, the pronghorn antelope, is rare. The most noticeable mammals here are the whitetail deer and the prairie dog (See pages 48-65 for pictures and text about the prairie dog and its predators) , but with careful observation you can spot some of the smaller animals that inhabit the grasslands, woodlands, and rocky areas around the Tower. ”

“ First, the pups must learn to engineer a burrow system with alternate escape routes. Second, they must learn to live in a highly organized social order, heeding its signals and respecting its boundaries.
Prairie dogs are divided into two general classes, the blacktailed and the whitetailed. Blacktails inhabit the semi-arid regions of the Great Plains; whitetails live in the higher elevations of mountain parks and foothills. But it’s difficult to generalize, for Devils Tower and Wind Cave National Park, in South Dakota, are in the Black Hills and the prairie dogs at both are blacktails. ”

“ Pups that annoy adult males with their attentions are often rather roughly groomed. No doubt the procedure communicates authority as well as affection.
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60 Dog Town Predators and Fellow Inhabitants
A shadow races across a prairie dog town, stirring up a sudden panic of alarms and dashes to safety. A shriek stills the community. Overhead, the squeals of an unwary pup rapidly diminish as it is carried off in a clutch of gleaming talons of a golden eagle, above, to a nest of hungry eaglets, below.
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Many pups and some adults are lost to predators. ”

“ On their own, prairie dogs cannot easily invade unbroken areas of established grassland. The grass cover simply rejuvenates faster than the animals can work. But if the land has been disturbed by overgrazing, prairie dogs can quickly spread. Once established in an area, the animals wage a constant struggle against the vegetation. Since tall-growing plants offer concealment to a predator, the plants are routinely clipped off even if they are not to be eaten. ”

“ However, they usually clip off all vegetation around their burrows even if they don’t eat it. This habitual grass-cutting apparently is defensive, for predators can conceal themselves better in tall grasses. That is why you don’t see prairie dogs in lush grasslands where there is a bountiful rainfall. They satisfy most of their needs for water with the juices of green plants and grass roots.
Prairie dogs also eat insects that inhabit their towns and sometimes prey upon the eggs or young of animals, such as the burrowing owl, that dwell in homes deserted by prairie dogs. ”

“ With a little last-minute help from fellow 33 workers, the ant carries its burden down into the nest hole. With its powerful jaws, another ant tugs the brittle remains of a once formidable foe—a jumping spider. So intent is the ant in its labor, it fails to avoid a deadly trap, however. In the soft ground along the margins of the trail is a craterfield of funnel-shaped pits. At the bottom of each, hidden just below the soil, waits quick death in the form of jaws even stronger than the ant’s. These insects, called antlions, are the larval stages of the equally voracious tiger-beetle. ”

“ Hopkins parachuted to the top and was stranded, keeping millions of newspaper readers in suspense over his fate atop the isolated rock monument few had ever seen. Durrance rescued his man five days later. Devils Tower again loomed in the national imagination, with the screening of the film “Close Encounters of the Third Kind.” And in 1979 a televised sports show featured George Willig, the “human fly,” whose climbing antics were beamed nationwide via space satellite. As we entered the decade of the 1980s the number of registered climbs of Devils Tower surpassed the 10,000 mark. ”

“ As the prairie dog pups soon learn, each coterie defends its own territory from intrusion by others, thus preserving for itself necessary living space and an adequate food supply close to the safety of its own burrows. Only in times of dire emergency, when the scramble to safety supersedes all territorial claims, will prairie dogs allow other coterie members the use of their burrows. So strong is an offending animal’s sense of trespass, it will often brave the hazard of dashing back to its own burrow rather than staying long in a neighbor’s territory. ”

“ The range of the prairie dog extends from Canada to Mexico and at its widest point from eastern Kansas to western Utah, with the blacktail’s range a bit more extensive than that of the whitetail. The range of the rare black-footed ferret, a predator, is nearly identical. The prairie dogs protected at Devils Tower are blacktails.
Each day the young spend more time above ground. Nearby, the mother remains alert for danger and solicitous, accepting the maulings of her playful and increasingly independent pups. ”

“ Early fall, just as the range begins to brown, is perhaps a perfect time to be at Devils Tower. The park is uncrowded after Labor Day. Protected meadows are still green. Animals are in their prime and ready for the rigors of winter. The faint odor of decaying vegetation and the foretaste of winter on a particularly bracing chill wind—these are the pleasures of a long Wyoming fall.
Winter brings an air of enforced isolation to Devils Tower. Heavy snows and frequent blizzard conditions on the highways discourage most travelers. A rare treat awaits those who do come here in winter, however. ”

“ I wonder if the climbers are as unprepared for this as I am.
In a rock crevice where the trail passes along a cliff face, an untidy ring of trash reveals the nest site of a wood rat. Called “pack rats” because of their habit of carrying off unguarded items, these big rodents adorn their nest entrances with anything from bottle caps to sunglasses. This one has amassed a fine collection of discarded gum and candy wrappers. As the first large raindrops thud down into the trail’s soft earth, I envy the animal’s protective retreat. ”

“ Today the top of the Tower is 386 meters (1,267 feet) above the Belle Fourche River. If that warm, Cretaceous landscape rested 600 meters (2,000 feet) above the present summit of the Tower, then more than 900 vertical meters (3,000 feet) of sedimentary rock has been pared away in the last 60 million years.
The relentless physical agents of erosion—running water, wind, and frost action—together with chemical breakdown of rock particles, continue to alter the landform. Given enough time, even the very hard rock of the Tower itself will waste away. ”

“ If the wave of alarms is particularly intense, the animals usually rush to burrow mounds, where they will await further developments. Usually only the 63 prairie dogs in the immediate vicinity of an enemy will retire below ground. The remainder of the population continues to observe and sound the alarm. As an enemy approaches a particular burrow, the frequency and intensity of the occupant’s warning bark increases. Only at the last moment will the prairie dog cut short its tirade, capping it with an indignant churk as it dives below ground. ”

“ Gold discoveries in today’s South Dakota portion of the Black Hills forced the final clash with the plains tribes. Custer had confirmed gold reports and the pressure of the excited rush that followed broke the government’s earlier treaty resolve to preserve forever the Indians’ sovereignty over the Black Hills.
Settlers carrying American civilization to the West by the overland route to California, Oregon Territory, and Mormon Utah then quickly flowed into this backwater area. ”

“ Whether herbivore, carnivore, scavenger, or decomposer, all of the countless, magnificently varied life-forms of each community share in the endless flow of chemical energy that originates with the touch of sun on chlorophyll. Eagle, prairie dog, bacterium, man—we all owe our lives, directly or indirectly, to the green leaf’s unique ability to convert light energy into chemical energy. ”

“ They, of course, contribute to the ongoing process of erosion which, over eons of time, has left Devils Tower in its present form. The amount of loose rock that breaks off under their feet, however, is far less than the amount lost every season from frost-heave, the effect of water seeping behind the surface rock and expanding into ice. The boulder field at the base of the Tower tells the rest of the erosion story. ”