Wikipedia:

Dipper | Dippers | Cinclus

Summary:

in the bird family Cinclidae. They are named for their bobbing or dipping movements. They are unique among passerines for their ability to dive and swim underwater. Dippers are small, stout, short-tailed, short-winged, strong-legged birds. The ...  (36 of 1309 words, 2 images)

Link:

http://en.wikipedia.org/wiki/Dipper  [cite]

Britannica:

dipper | water ouzel

Summary:

any of five species of songbirds of the Cinclidae family noted for insect hunting by walking underwater in rushing streams and named for their ...  (24 of 100 words)

Link:

http://www.britannica.com/EBchecked/topic/164695/dipper  [cite]