"Here the river surges over and around boulders the size of Volkswagens. The churning whitewater roars in your ears. It buckles your knees. It wants to knock you over... Around the bend, the water flattens into a long smooth glide. Here you can hear warblers chirp in the alders and see trout dimple the surface.... There are soft spots behind each of those boulders, cushions in front of them, and smooth, food-carrying runs where the currents funnel between the rocks.... These soft little pockets give trout everything they want: Comfortable places to rest, protection from predators, cool, well-oxygenated water, and a continuous supply of food."