from an essay by Jeanetta Calhoun Mish
A PLACE OF DUNES
The earliest known published account of what is now the White Sands National Monument appeared in The American Naturalist in 1870:
Salt Plains of New Mexico.—Brevet Major General August V. Kautz, U.S. Army, writing from Fort Stanton, New Mexico, informs me that there is a valley of some two hundred miles long and twenty wide, lying between the Sierra Blanca and the San Andreas and Occura [sic] mountains, in that Territory, in which there is no stream, and only a few alkaline springs and salt lakes, or ponds. Where the road from Ft. Stanton to El Paso crosses it, about sixty miles south of that post, is a plain of white sand, apparently granulated gypsum, which has drifted into mounds, forty and fifty feet in height. Water of a strongly alkaline character is obtained by digging a few feet, and around the edges of this district, salt marshes exist, where in the dry seasons, great quantities of almost pure salt may be collected. The sand is so white and the plain so extensive as to give the effect of snow scenery. As I do not remember to have seen a description of the place in print, I send you this note with a specimen of the sand forwarded by General Kautz. —George Gibbs, New York
Strictly speaking, the White Sands are an erg(sand sea), a term defined as an area that contains more than 48 square miles of aeolian(wind-blown) sand. The white sands dune sea is 275 square miles, 27 miles long and on the average 10 miles wide. Unlike other natural formations like mountains, dunes move at a human-recognizable rate: the most active ones are moving toward the northeast at a rate of up to 30 feet per year, pushed along by prevailing winds that blow from the southwest (NPS “White Sands”).
Dunes are categorized by their shapes, and of the six primary types of dunes, four are present in the Monument: dome, barchan (crescentic), transverse, and parabolic. Dome dunes are just what they sound like, low mounds of sand. They are found immediately downwind of Lake Lucero, being the first dunes to form from the gypsum sands. It is the dome dunes that are moving at 30 feet per year. Barchan dunes are crescent shaped, transverse dunes are made up of several barchan dunes joined together, and parabolic dunes are the mirror image of barchan dunes, created when plants grow into the dune, holding the arms of barchan dunes in place, causing their shape to invert. Barchan dunes offer an insight into how all dunes are formed: dunes form wherever the wind slows down—when the wind slows down, it drops its load of sand particles. Anything from a depression in the landscape to a plant to a rock can slow the wind down enough that sand drops out.
In another, more-difficult-to-explain mechanism of dune building, the sand itself can cause its own accumulation by slowing down the wind that carries it and through sand grains’ collisions with other sand grains and with forming dunes. Once a sand dune has reached a certain thickness and angle (known as the angle of repose), avalanches begin to occur, and sand tumbles down the dune on the “slipface” or leeward (downwind) side, a process which, through repeated avalanches, moves the dune forward, and the process of dune building begins again.
The language of dunes is poetic: parabolic (the mathematical representation of a gravitational effect), barchan (from the Kazakh language), both crescent-shaped like a waxing or waning moon. Dome like a cathedral’s cupola vault, designed to mimic the eternal heavens. Aeolian, a word come down to us from the Greek god Aeolus, the god of wind—dunes are aeolian structures, meaning they are created by the wind. Ah, but “angle of repose” is the most magical phrase of all. The angle of repose in this case is not the position I take when reading poetry on my couch; instead, it is the steepest angle to which a dune (or loose rock or snow other granular material) can be piled without slumping, without grains beginning to tumble down the slope. Think of this when you walk the dunes—look for the tiny avalanches that presage larger avalanches. Contemplate that, as you think of the angle and the impending avalanches, you, yourself, are in repose—in a state of tranquility. You have become one with the dune.
Dune fields are living, breathing, moving macro-organisms. They are ecosystems; that is, they serve as habitat to animals and insects and plants; the dunes at White Sands, no matter how desolate they may look, are no exception. The interdune area—the mostly level sand sheets between the dunes—are essential to the flora and fauna of White Sands. The water table in some interdune areas is so close to the surface that a freshly dug shallow hole will fill with water, albeit water not drinkable by humans. Here, in these areas that are sheltered from the wind by the dunes and where groundwater is close to the surface, is where most of the plant life of White Sands puts its roots down.
The NPS White Sands website informs me that there are six distinct ecological units in the White Sands, each of which has its own array of plant life. Among the wildflowers you might see at White Sands are the Centaury (not the century plant, but a pink gentian), wooly paperflower, sand verbena (which smells like lilac), stick-leaf, and yellow evening primrose. Soaptree yucca is also a common plant in the dunes. It has evolved to stay ahead of the encroaching sand by elongating its stem whenever a dune threatens to overtake it, growing toward the sky as much as a foot per year. Skunkbush sumac and hoary rosemint can do the same, just not as quickly as soaptree yucca. Dunes that are more stable are hosts to, among other plants, the lovely light pink blossoms of ephedra, the happy yellow-blossomed greenthread, the scarlet “claret cup” hedgehog cactus and the purplish feathery seedheads of alkali sacaton bunchgrass.
The most unusual plant in the dunes is the night-blooming cereus (Cereus greggii), a member of the cactus family. When it is not blooming, the plant’s gray stems can appear to be dead. But, once a year, the cereus—la Reina de la noche—pushes out elongated buds and on one night, for only one night, the cereus blooms, and all the cereus plants in an area bloom at the same time. The white, double-petaled flowers fill the air with a scent sometimes described as an intense vanilla.
Let us consider now the Queen of the Night. How does she intuit the perfect evening to unfold her expansive, waxy blossom? And how does she tell her sisters it is time to unwrap their corsages? She waits four years or more to send out her first bud and then waits again for the perfect summer night when the stars sing una canción rancherato the sky. All the sisters hear the song and open their white flowers at once, like a hundred embroidered silk handkerchiefs dropped for a gentleman’s attention. La Pavura Blanca, attracted by the flowers’ rich perfume, whirls by and picks a single white blossom to pin in her hair before continuing the search for her beloved.
It’s not only plants that make their home in White Sands National Monument: there are approximately 144 species of birds, 23 small mammals, 371 species of insects and several types of reptiles in the dunes (Dodge, 5-6). Badgers, kit foxes and grey foxes, porcupines, and cottontails and jackrabbits are common in the dunes, as are pallid bats and four species of pocket mice. Several species of lizards and snakes live in the dunes, including the nonpoisonous western coachwhip and Sonoran gopher snakes and the poisonous western diamondback and prairie rattlesnakes. There are even toads and one species of fish, the endangered White Sands pupfish, which lives in Lost River, a stream that enters the Monument dunes from the east and then, after about two miles, disappears into the sands (“White Sands Pupfish”).
Among the small mammals of White Sands is the Apache pocket mouse which has evolved to be lighter in color than its counterparts in other places. Similarly, the pocket mouse in the Malpais is a darker color than it is in other habitats. Camouflage is an important adaptation for survival of the little mouse whose buff white fur matches the sand, making it more difficult for predators to see him. The Apache pocket mouse isn’t the only dunes animal to make use of camouflage coloration—the bleached earless lizard, the little-striped whiptail lizard, the Cowles prairie lizard, the spotted ground squirrel, and two species of camel crickets have all evolved to a permanently lighter color after generations of living in White Sands (“White Animals at White Sands”).
Bird life in the white sands and surrounding areas is much more diverse than one might imagine. Birds commonly seen at the sands include the wise and talkative Chihuahuan Ravens which surely carry on important conversations with Northern Mockingbirds and Western Meadowlarks. Of the raptors who hunt the white sands, the Northern Harrier and the American Kestrel are most often in the skies. White Sands birds range in size from the Great Horned Owl, whose adult wingspans can reach 5 1/2 feet, to the tiny Say’s Phoebe whose entire body is only six inches long. The fancy-flying Common Nighthawk likely inspired more than one airplane, like those which rule the airspace in the Basin. Then, there is the beautiful desert cardinal, which looks like a cardinal with reversible feathers: they are mostly gray, with cardinal red accents. There are other birds which are not as common at White Sands, but visitors should stay alert—they might be lucky enough to see one of the rare species, like the West’s fanciest dresser, the Violet-green Swallow or, perhaps, the majestic Golden Eagle.
There are flora and fauna in the White Sands area that are not native but have been introduced, and strangely enough, two species were introduced by agencies charged with protecting New Mexico’s plant and animal life. In 1966, the New Mexico Department of Game and Fish introduced the oryx, a large African antelope, to White Sands Missile Range in order to provide hunters with big game (Dunes and Dreams). Free of their natural predator, the African lion, oryx flourished in the Tularosa Basin, expanding into the National Monument area, and are now a nuisance animal which overgrazes and damages the native plants in the area. Yearly oryx hunts on the Missile Range have been unable to fully control the population, and the Monument has had to resort to large fences to keep the oryx out—but tracks seen on a trip to Lake Lucero in 2013 suggest that the fences can’t entirely control the oryx, despite the best efforts of park employees. Similarly, between 1899 and 1915, the U.S. Department of Agriculture introduced the tamarisk, commonly called exotic saltcedar, to the Southwest—it has run amok wherever water and saline soils are found. Although it is a lovely tree covered with clouds of pink blossoms in the spring, it grows and spreads quickly, choking out native plants and monopolizing available water. However, the agencies involved are now trying to control or eradicate both the saltcedar and the oryx. And, many of the agencies concerned with wildlife, including the military and tribal groups, are participating in the re-introduction of the Desert bighorn sheep to northern New Mexico and the Mexican gray wolf to New Mexico, although the White Sands Missile Range is a “backup” area for future releases. The program has brought the wolf’s numbers in New Mexico up from zero identified individuals and breeding pairs in 1998 to eighty-three individuals and five breeding pairs in 2013 (“Mexican Wolves in the Wild”). Beginning in 1999, the New Mexico Department of Game & Fish captured and relocated desert bighorn sheep to the San Andres mountains, just west of White Sands. In 2015, there were an estimated 115-135 bighorn in the San Andres.
We humans are so anxious to meddle. We often mean well—the saltcedar was meant to hold back the banks of rivers, the oryx, well, the oryx was meant for sport, for human recreation. The Mexican gray wolf was near extinction because we brought our cattle to the Basin and to a wolf, a cow looks like dinner, and so was exterminated for being hungry. Not so much different, then, than those who brought the oryx to the basin for the hunt. White Sands should give us pause: the earth has been maintaining itself and revitalizing itself and remaking itself for millennia without our intercession; perhaps we need to think in centuries instead of years.
Text Copyright ©Jeanetta Calhoun Mish. All Rights Reserved