The column moves languidly, dust clouds swirl above like trailing woodsmoke. Twenty cowboys driving 2,000 head of cattle on the trail from Texas to New Mexico slowly disperse into their overnight encampment. The summer breeze blows lightly, fragranced with the smell of prairie grass. Thunderheads gather on the horizon like great floating avalanches. Near the chuck wagon, a flank rider notices they are being watched. In the distance, antelope—hundreds of pronghorns—watching with nervous curiosity, their stark beauty in contrast to the muted landscape. The cowboy watches wistfully, admiring this magnificent display, this miracle of nature. Suddenly, white rumps flash in the afternoon light while a flurry of elegant hooves sweeps the antelope herd out of sight. The slightest wisp of dust lingers, only dreams of running wild and free with no boundaries remain.
Found only in North America, pronghorns were once as abundant as bison in the American west. Being the only surviving members of a group of animals that evolved during the past 20 million years, despite the tag “antelope,” pronghorns are not true antelope. The pronghorn’s closest living relatives are the giraffe and okapi. Intensely aware, pronghorns can detect movement up to 4 miles away and, when alerted to danger, can contract their rump muscles raising white rump hairs on end. This “flashing” can be seen by other pronghorns from as far as 2 miles away. Their most effective defense, however, is speed. A mature pronghorn can outrun almost any other animal on earth and is considered the second-fastest land mammal in the world, after the African cheetah. Top speed depends on the time interval measured; by comparison, pronghorns can sustain relatively high speeds for much longer than cheetahs. Bottom line: they are wicked fast!
Today pronghorns are found exclusively in the lower 48, mostly in the Great Plains states. Some of the highest numbers are in Wyoming’s Red Desert and Yellowstone ecosystems as well as northern Colorado. Texas has a dwindling herd. All told there are five subspecies, two of which are in Texas. The Texas range for pronghorns is highly fragmented with isolated pockets throughout the Panhandle and the Trans-Pecos regions. Some of the best places to see Pronghorns are just south of Marfa, and between Alpine and Fort Davis. From Marfa, as you move north look for pronghorns grazing alongside cattle on the plains north of Alpine on both sides of the road leading to Fort Davis. The mature buck in Texas stands about 3 feet tall at the shoulder and rarely exceeds 110 lbs. Females are daintier. Markings are tawny brown with strident white neck stripes, underbelly, and rump. The face is distinctively tri-colored black, white and tan. Bucks have a black patch at the corner of their jaw. They are magnificent creatures—proving that natural beauty outranks art every time!
Pronghorns are classified as game animals in all the western states, so permits are required to hunt or trap them. They are legally hunted for purposes of population control and food, although sadly (and, perhaps more truthfully) they are high on trophy-hunters’ hit lists because of their exquisite markings. No major range-wide threats exist to the pronghorn population in general but there are localized declines—like in Texas. It is estimated that numbers in Texas have dwindled from hundreds of thousands in their heyday, to roughly 12,000 today.
Reasons for population decline in Texas are complicated and interconnected but are mainly a result of livestock overgrazing, construction of roads, fences and other obstacles, poaching, and insufficient forage and water. West Texas is a tough environment. Drought and lack of rainfall increases competition for forage. Lack of plentiful forage not only causes malnutrition and starvation but also means insufficient fawning cover to hide vulnerable fawns from predators like coyotes in the spring and summer. Pronghorns are traditionally a migrating species, moving to better grazing in winter. Because of fences and roads, movement from the Trans-Pecos area to the northern plains is a problem. Pronghorns don’t know they have the ability to jump fences; instead, they crawl between or under them. Even a 3-foot-tall fence will often keep them contained. Fencing is a serious problem to free movement, denying them access to protection from inclement weather, additional food, and adequate fawning cover. Coyotes haze pronghorns toward fences and catch them as they get tangled or are slowed crawling through. Rarely do pronghorn survive traffic when seeking access to forage through our highway rights-of-way. The wide-open spaces in Texas are no longer so wide open.
Why the name pronghorn? There is no other animal in the world with horns that branch like prongs, curved at the tip. Adult males typically have 10-16-inch horns which are really fused hair growing over permanent bony cores. When females grow horns (not all do), they are seldom tall enough to be pronged. Males shed their horns each year, like clockwork. Female horns are eventually shed but at various times.
Most farm animals would not be able to survive on what pronghorns eat. Although their diets vary from season to season, pronghorn favorites are native flowering plants, including varieties known to be poisonous to sheep and cattle (e.g., locoweed, poison vetch, lichens). Juniper bark, broom weed, and selected spring grasses are also on the regular menu. Sagebrush, rabbitbrush and other desert plants fill in during winter periods. Pronghorns have a liver that is proportionately almost twice the size of a domestic sheep’s liver, perhaps giving them the ability to eliminate plant toxins from the blood stream. Given this harsh diet, it makes sense that pronghorns are ruminants which process foods through multiple-chambered stomachs. In other words, they “chew a cud” (regurgitated, partially digested food), like cattle. Pronghorns seldom drink because most of their water comes from the plants they eat.
Because of their long-range migratory routes, pronghorns are the true marathoners of the American plains. Several herds with about 400 pronghorns make a 300-mile round trip each year in the northern states. In November, snow gathers in deep pillows on spruce boughs in Wyoming, and the herd knows it won’t be long before it’s food source will be completely covered. In small herds, they start migrating south from Grand Teton National Park across government land, private lands, and ranches on their way to the Upper Green River Valley. In April, they make the journey back. Migration like this is an increasingly rare phenomenon worldwide, but certainly in the U.S. A recent joint study by the Lava Lake Institute for Science and Conservation and the Wildlife Conservation Society tracked an overland migration route from the foothills of the Pioneer Mountains through Craters of the Moon National Monument all the way to the Continental Divide. Idaho was shown to be a major corridor for the animals.
Not all pronghorns migrate, either because the nearby land has plenty of food all year or because of barriers to movement, like in Texas. The National Wildlife Federation and its affiliates are working hard to open up corridors for pronghorn and other migratory wildlife while trying to reduce conflicts between animals and people.
Pronghorns live about 10 years, rarely 15. Being selected for mating seems to be Mother Nature’s tacit nod to the worth of natural selection. Of course, sexually mature pronghorns (yearlings) take steps to help ensure inclusion in the great arc of parenthood. It starts off benign at first with the urge to mate reaching fever pitch by September. Males less than 3 years rarely breed, females are receptive at one year. By mid-fall those who will be impregnated have been. Gestation is usually around 7 months. Pronghorns form mixed-sex herds in the winter then break up into cliques by early spring. Young males segregate themselves into bachelor groups, females form available harems, and adult males strike out on their own. All adult males either defend a fixed territory that females may enter or defend a harem of females. One energetic buck may entertain a harem of a dozen does. Dominant females aggressively run off other females from choice feeding sites. When it comes to reproduction, you’re either in or out.
By May or June, a pair of 6-pound. grayish-brown twins appear. They can walk within 30 minutes of birth and can outrun a human in a couple of days. Mothers hide their helpless young and return to them to nurse periodically throughout the day. By three weeks, fawns are following their moms and nibbling vegetation; at a month they are grazing independently. Several females and their youngsters will usually join to form nursery herds, along with yearling females.
Despite restocking programs instituted by TPWD, the population of pronghorns has steadily declined while their range in Texas has almost disappeared. How many animals have we extirpated from Texas for money or sport in the last 100 years? What can we do to save these exquisite animals? At this point, probably nothing—except open up corridors and stop hunting them!
By Larry Gfeller