Five species of birds compose the Cinclus genus, all of which have a very unique characteristic: They dive underwater to catch small fish and invertebrates, along with their eggs and larvae. They are most commonly found along river banks and fast flowing streams. Being able to swim underwater, they bear adaptations for this purpose. For instance, their bones are solid to reduce buoyancy, while the feathers are dense and covered in oil that repels water, which has two effects: Maintaining the body dryers, and capturing a small layer of air around its body. The White-capped Dipper in particular is dark gray on the upper side, white on the underside and shows a white cap that goes well with its common name.