Life on the Edge
Gravity-defying acrobatics help mountain goats survive in a world of sheer cliffs and icy winds
Douglas Chadwick watched as the mountain goat strolled along the narrow, tapering ledge high in Montana's Swan Mountains. Sheer rock walls loomed above and below the wisp of a trail, which finally petered out altogether, bringing the animal to a halt. So slender had the ledge become that the goat now had no room to turn around, or even space to pivot and peer over its shoulder for a slow, backward retreat. To the biologist looking on from below, the shaggy white creature appeared to be in quite a jam.
Then the goat performed a stunning maneuver. Bracing its front hooves, it carefully walked its rear legs up the rock wall and over its head in a slow-motion cartwheel. In a moment, the animal was back on all fours, facing the opposite direction. It leisurely left the way it had come. "I sat there dazed with my mouth hanging open," says Chadwick. "I had trouble believing what I'd just seen."
What the Montana scientist had just seen was simply business as usual for the mountain goat, a supremely sure-footed creature that thrives in a narrow, high-country niche where few animals other than birds dare even visit. Uniquely adapted in every respect to its rugged and inhospitable habitat, the goat is the unquestioned king of the mountain.
Ironically, the treacherous terrain it inhabits is also the creature's greatest adversary, far more fearsome than the cougars and other predators it usually leaves far below. And lately, people have started showing up in goat habitat, a development that scientists fear may threaten the reign of this alpine monarch.
The mountain goat, or Oreamnos americanus (American mountain lamb), is the only member of its genus. Neither true goat nor sheep, it is actually a distant relative of Europe's chamois and the serow of Asia, though it now lives exclusively in North America. Billies (males) weigh about 200 pounds and stand some three and-a-half feet tall. Nannies (females) are smaller by 50 pounds and a few inches. The legs of both sexes are short, providing the low center of gravity essential for death-defying leaps.
With bulky, muscular forequarters and small haunches, the goat looks something like a miniature bison, and it walks with a stiff, bearlike swagger. A 5-inch beard lends its countenance a professorial air. Three inches of cashmerelike wool and long, hollow (and thus insulating) outer guard hairs provide protection against temperatures that can dip as low as—40 degrees E The goat's regal white attire is a camouflagic adaptation to habitat spotted with snow nearly year-round.
Although mountain goats sometimes frequent lower elevations, their normal home is a stark alpine aerie above the timberline and sometimes as high as 10,000 feet above sea level. Theirs is a land of wind, ice and snow, of pinnacles, ledges and landslides. Goat habitat is so dangerous that nannies habitually position themselves below their kids to keep the youngsters from tumbling to their deaths. "It makes me nervous just to watch them," says Victoria Stevens, a Canadian biologist and consultant who studied goats for eight years in Washington State.
Doug Chadwick spent several years observing goats, mostly in Montana, and subsequently wrote a book about them. For a picture of mountain goat habitat, he says, start by imagining a typical staircase. Then tilt it upward severely, take out most of the steps and shovel ice and snow over the whole affair. Finally, position this staircase atop a building so that the next step down involves a two-story fall. The question of survival, he says, "must be answered foothold by foothold throughout much of each mountain goat's life."
North America's first mountain goats likely emigrated from Asia, crossing over the Bering land bridge thousands of years ago. Today, the animals range naturally only in Alaska, western Canada, Washington, Idaho and Montana, but relocations have established dozens of populations elsewhere in North America.
Although difficult to count, mountain goats probably number between 40,000 and 100,000, most of which live in British Columbia and Alaska. Nowhere, though, is the goat's success more apparent than in Washington's Olympic National Park. In the 1920s, state authorities released a dozen of the animals in that state's then goatless coastal mountains. Later, when part of the area was designated as a park, the goat population swelled to 1,100—so many that native plants began to suffer from overgrazing. "We now see the mountain goat as an undesirable component of our fauna," says park biologist Doug Houston. So far, 700 goats have been moved to goat habitat in Washington and nearby states, and officials are currently trying to decide how to manage the rest.
Perhaps because the slightest misstep can mean immediate death, mountain goats have evolved a rather phlegmatic life style. Goat watchers say—with only a little exaggeration—that the plodding animals never lift more than one foot off the ground at a time. Forced to run, they are capable of short sprints, but tire quickly.
Supplanting speed is a methodical, go-anywhere climbing ability that leaves all other four-footed creatures far behind and below. When the nearest solid footing lies two leaps away, a goat may jump to a spot where it cannot remain, then leap again before loss of momentum would send it crashing to its death. Through it all, the shaggy mountaineer remains unflappable. "Just when you imagine that the goat you're watching must be clinging for dear life to a shred of ledge," says Chadwick, "it calmly lifts a rear foot and begins scratching an ear with it."
Even when goats fall, they maintain exquisite poise. While studying the animals in Washington in 1979, Michael Hutchins, a biologist with the American Association of Zoological Parks and Aquariums, saw a nanny slip and fall from a cliff. Fortunately, just 4 feet below her ran another ledge. By the time she landed she was already upright, and with hardly so much as a blink she ambled peacefully away. "I don't think she missed a step," says Hutchins, who, along with Chadwick and other researchers, suspects that goats possess nothing akin to human acrophobia.
One important key to goat agility lies in the creature's feet. Unlike the hard, concave hooves of deer and other ungulates, goat feet are convex, rubberlike pads. Pressed against a rock, they grip like high-priced tires. The two toes on the front of each foot splay outward, functioning as brakes when the animal moves downhill. Powerful forequarters add another dimension to goat mountaineering. Like a human climber, a goat may reach above its head, hook a hoof on a rock, then pull itself up. Such maneuvers, says Chadwick, "amount to one-handed chin-ups."
Goats are born acrobats—almost literally. In May or early June, pregnant nannies find a secluded shelf and give birth to a single kid (or sometimes twins). Ten minutes later, the youngster is on its feet. Within hours it can climb rocks. "Goat kids are extremely precocious," says Gayle Joslin, a wildlife biologist who has studied goats for ten years for the Montana Department of Fish, Wildlife and Parks. "Within a day or two, the kid starts following mom around, and after a week it can go almost anywhere she does."
That takes in a lot of territory. While studying mountain goats in Montana's Glacier National Park in 1978, for example, wildlife biology student Ursula Mattson spent the night in a lookout tower high atop remote Mt. Brown. Awakened the next morning by footsteps on the catwalk immediately outside, she found herself face to face (separated by a window) with a nanny that had climbed the steep stairs to see who was intruding in her domain.
"I've even seen goats climb into the lower branches of trees to escape perceived danger," says Joslin, pointing out that helicopters and sonic booms often send goats treeward. Cougars, wolves and a few other four-legged predators occasionally kill goats, but eagles may be the greatest threat, especially to kids.
One June afternoon in 1948, the late Idaho biologist Stewart Brandborg, who conducted one of the first and most exhaustive studies of mountain goats, caught a rare glimpse of eagle predation. As he watched, a bald eagle suddenly landed a few feet from a group of five goats feeding along some cliffs west of Augusta, Montana. One nanny left her kid and moved to confront the bird. Immediately the eagle took off, snatched up the kid and glided over the cliff and out of sight, its limp prey still dangling in its talons. The biologist estimated the young goat's weight at about 7 pounds.
Goats don't always end up the losers in a confrontation. Both sexes are outfitted with pairs of 9-inch, daggerlike horns, which they use to fend off attacking eagles and even large cats. In general, though, predation plays but a minor role in the lives of mountain goats. "When goats are in the cliffs, even a cougar or grizzly must pause and think about whether it is that hungry," says Houston.
Yet goats pay a price for a habitat largely free of enemies. Although they are masters at eking a living from a stingy land, food can be hard to find in alpine crags, and winter starvation kills many of them. So does the terrain: Brandborg had often found dead goats at the base of cliffs, rock slides and avalanche chutes—apparently victims of their habitat.
Goats also must be wary of each other, especially when they are disputing personal space or rights to a salt lick. At a lick in western Montana, Joslin once saw a nanny pick up a kid with its horns and casually toss the youngster aside like a sack of flour. "I can't be sure," she says, "but that nanny might have been the kid's own mother."
Quarrels that erupt between goats during the November rut can lead to serious injury or even death. "The sole function of goat horns is to penetrate and maim an opponent," explains Valerius Geist, professor of environmental science at the University of Calgary in Alberta and a longtime student of goat behavior. In the body of a dead billy he found years ago in Alberta's Banff National Park, Geist counted 32 stab wounds, including punctures of the lungs and heart.
To defend themselves against the lance thrusts of opponents, billies develop what Geist calls "a kind of armor"—skin nearly an inch thick on some parts of the body. "But," he says, "bloody battles are very rare. Most confrontations consist only of ritual and psychological warfare." A more serious problem for goats is the creeping human invasion of their habitat.
Historically, the remoteness of goat terrain kept people out, but increasing demand for resources is changing that. "The real rugged country isn't sacrosanct any more," says Joslin. "There's a new industrial push into formerly impenetrable habitat, and some goat herds are suffering."
For example, just the exploration for oil and gas (not actual production) apparently upset goat reproduction, causing the animal's population in one area of Montana near Glacier National Park to drop by 50 percent between 1981 and 1985. Helicopters roared through the air, and seismic blasts occurred every few minutes, making the area sound like a war zone.
In British Columbia and Alberta, disturbances related to timber harvest have virtually wiped out some goat populations. "The problem," says Joslin, "is that goats are fragile, rigid, unadaptable animals." Therein lies a paradox: While goats may be resistant to change today, over the millennia they have adapted perfectly to their tenuous perch on top of the world.
Despite increasing threats to their mountain home, goats continue to thrive in the habitat that remains—a fact that only enhances their image as near-mythical beasts seemingly capable of impossible feats. As naturalist Ernest Thompson Seton once remarked after watching a particularly spectacular display of goat agility: "It would not have surprised me in the least had the goat soared away over the tops of the trees."
Sure-footed Missoula writer Gary Turbak occasionally hikes into Glacier National Park to watch mountain goats like the ones photographed for this article by Montana residents Alan and Sandy Carey.
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