Gravity-Defying Goats
Photograph by Adriano Migliorati/Caters News
Using moves that would make any rock climber jealous, Alpine ibex cling to a near-vertical rock face of a northern Italian dam in summer 2010.
This and other pictures of the goats have been circulating online recently, particularly in emails claiming the animals are bighorn sheep on Wyoming's Buffalo Bill Dam, the rumor-quashing website Snopes reported in September.
In truth, Adriano Migliorati snapped the pictures at the 160-foot-tall (49-meter-tall) Cingino Dam (see map of the region), the Italian hiker told National Geographic News via email. The goats are attracted to the dam's salt-crusted stones, according to the U.K.-based Caters news agency. Grazing animals don't get enough of the mineral in their vegetarian diets.
It's not far-fetched, though, to think such a scene could be photographed in the United States. For example, mountain goats could scale dams in the U.S. West, according to Jeff Opperman, senior advisor for sustainable hydropower at the U.S.-based nonprofit the Nature Conservancy.
Opperman, who called the Cingino pictures "mind-boggling," pointed out a picture of a Montana mountain goat doing an "incredibly acrobatic stretching maneuver to lick salt" in the November National Geographic magazine.
"He is wedged up this sheer vertical cliff face, almost doing a yoga pose with four hooves splayed out there," he said. "It's the same concept [with the Italian goats]—these animals can overcome what looks like impossible topography to get what they want."
Opperman cautioned, though, that the Italian dam is rare, in that its rough masonry provides gaps that act as toeholds. The more common, smooth-concrete dams—such as Cingino Dam isn't completely vertical, allowing ibex—such as these goats pictured in summer 2010—to gain some purchase.Adapted to their perilous environment, Alpine ibex have evolved a specialized split hoof, whose cleft is wider than on any other split-hooved species, according to Smithsonian Magazine. The hoof also has a hard wall that can grab on to steep cliffs and a soft, rubbery inside that serves as a "stopper" when the animal is pushed forward by gravity, the magazine reported.
And because dams are usually built in steep canyons, Cingino's steep rock face is likely nothing novel for the mountain-dwelling ibex, according to Opperman.
Sometimes reaching heights of 16,000 feet (5,000 meters), the herbivores spend their lives scrambling the European Alps' rocky and steep terrain, according to Caters news agency.
Buffalo Bill Dam— would give goats anywhere in the world trouble, he said.
By scaling Cingino Dam, salt-craving ibex, such as this animal pictured in summer 2010, are "showing ingenuity, taking advantage of this human-created thing in their environment," the Nature Conservancy's Opperman said.
Some other enterprising species can also work around dams in their habitats. For instance, eels can literally wriggle up some dams obstructing their paths, Opperman noted. But all too often dams act as barriers for wildlife, for example by blocking migrating salmon and other fish.
"When we think about dams, it's often [about] these weighty issues," such as balancing energy needs with wildlife protection, Opperman added. The goat pictures are "a whimsical, comic relief to that."
Published November 1, 2010
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