The American Dipper (Cinclus mexicanus) is commonly known as the Water Ouzel and was John Muir's favorite bird. Indeed, few birds are as fun to watch as ouzels. They are the only bird in the Sierra that will dive straight into rushing water to feed on insects. They appear to run along the bottom, "flying" in the water. When above water, they do a funny little dance as they bob here and there.

Here are a couple of videos showing an American Dipper (Cinclus mexicanus), aka Water Ouzel, swimming and a second one showing the bird. I also have a few photos below the videos.

Ouzel swimming

This would be better if I had a polarizing filter, but you can get some idea of how an ouzel cavorts in the water.

Ouzel bobbing

The very end of this clip shows the distinctive little dance that the American Dipper does.