Downcanyon: A Naturalist Explores the Colorado River through the Grand Canyon

Every writer comes to the Colorado River in the Grand Canyon with a unique point of view. Ann Zwinger's is that of a naturalist, an "observer at the river's brim."

Teamed with scientists and other volunteer naturalists, Zwinger was part of an ongoing study of change along the Colorado. In all seasons and all weathers, in almost every kind of craft that goes down the waves, she returned to the Grand Canyon again and again to explore, look, and listen. From the thrill of running the rapids ...