Times you turn into an eagle counter or an urban park ranger. You’re on your own, a fox, a gypsy moth. Near Cañon City, Colorado, the highest bridge in the US spans Royal Gorge, acts as a magnet for melancholy—a tourist might actually see someone jump. Search and rescue is harder to find. Local firefighters are exhausted. “We’re not like other species,” you say, a river guide, a novelist at night. Your fellow rafters nod, though no one knows for sure what you mean. “Be on the lookout,” you add, with a dip of your paddle. Swallows miss you by inches, iridescent and soaring. The river’s a prism of three million years, the silence after rapids tremulous. Rocks rise a thousand feet into unforgiving air. This kind of life keeps breaking your heart.