The Black Redstart was originally a pure rock dweller which, however, profited by increasing urbanisation and the spread of settlements and presumably began to nest in our towns and villages in the 18th and 19th century. Black Terns remind one of large swallows with their elegant and somewhat choppy flight banking from side to side. They mostly fly in loose flocks and snatch their prey off the surface of the water in a low wavy flight, whereby they keep changing their body position, direction and wing beat frequency.