Mist curls, rises, swirls over the Snake River in the light of early dawn and a full moon. It is the morning of the autumnal equinox. The air is calm and chilly, about 42 degrees. A touch of autumn color tints a few trees. Pileated woodpeckers and a northern flicker sound their ringing calls in the woods. A small group of black-capped chickadees gurgle softly to each other as they hunt for insects in the hazelnut bushes on the riverbank. In a few minutes, the sun will rise, the mist will vanish and the day will gradually warm to 70 degrees. But for now, the river valley is hidden and serene.