Unusual for a songbird (or passerine) this Eurasian dipper swims underwater searching for food (aquatic invertebrates, including mayfly nymphs and caddisfly larvae). It can also walk on the riverbed held down by the force of the current when it angles its wings against the flow.
I'm fortunate to have this stream (see below) at the end of my garden where dippers breed and their delightful warbling song starts in the Autumn.
The singing brings added charm to the sound of gurgling, bubbling water as it tumbles over the stones and rocks.
(Other dipper species around the world are also available. )