Birds bathe to maintain their plumage. Water helps remove excess oil, dead skin, parasites and dust. All these things prevent the feathers from working at their peak performance for flight and body temperature control.

Bathing often follows a pattern of wading, fluffing feathers to expose skin, and moving wings in a splashing manner. Next the breast is lowered into the water, the head is raised and the wings extended, which helps soak the skin of his back as he raises and lowers feathers. The bird often repeats these steps, getting wetter and wetter.

After the bath, the bird will shake, flick his wings and tail, and ruffle his feathers. Preening is the next step in the grooming process. The house sparrows at the bird bath took flight and did their feather arranging out of camera range, probably while resting on a tree branch.