High above Valle Chacabuco on a massive sandstone bluff, I spy a hundred miles distant the northern ice fields, their jagged and unruly peaks unnamed and almost entirely unclimbed. I see lush river valleys below and the rising Patagonian steppe as it moves into Argentina. Above me, a lone adolescent male guanaco screams and spits at me, annoyed by my intrusion. And above him, two condors soar on thermals, their 10-foot wingspans barely moving.

I run on a dusty guanaco trail, around me slow and fat horseflies buzz. Two hundred feet below, I gaze upon an ancient beech forest. On the limbs of their sun-bleached, gnarled branches lay reams of Spanish moss. I veer down, into the forest where temperatures feel cooler, where the driving sun does not penetrate the low canopy.

Now, winding my way through the short, stubby trees, I see to my right a family of brightly colored parakeets. Off to my left, I hear the tap, tap, tap of an enormous Magellanic woodpecker, his outrageously red head pecking rhythmically on his favorite beech tree.

And then, several hundred feet later, I hear absolutely nothing. I stop again. The loud cries of the parakeets, the booming tap of the woodpecker, the bleating of the guanaco – all gone. Enlightenment of the worst kind washes over me. The high hills belong to the guanaco, the skies to the condor and the forests to the puma. I run again, perhaps now for my life.

We are here to remove fencing, 400 miles in total at the rate of roughly half a mile a day, restoring natural migration paths. Today, a baby guanaco got caught in a fence, suffered and died alone. The fence he died on is the same fence we are pulling, but pulling too late. I hike out to see the body, but the condors have already stripped him to bone. Nature is ruthlessly efficient in Patagonia.