A chocolate-brown, short-tailed thrush-like bird of clear, flowing streams. No other stream bird in its range is dark brown all over (adult) or dark brown mottled with pale (juvenile). Plunges into streams, swimming and diving to capture prey like a seabird. Seldom found more than a few feet away from water. Uses any moving water so long as it is clear and open--even hot-spring fed pools in the dead of winter. Song a rich and variable series of trilling and rattling notes. Often gives a buzzy “zeet” in flight.