The swans in the moat at the Bishop’s Palace in Wells, Somerset, pull a bell for their lunch. The tradition is believed to have started in the 1850s — in 1908 Helen Pratt wrote:

This bell-ringing call was taught to the bishop’s swans more than fifty years ago, by Miss Eden, the daughter of the Lord Auckland who was then Bishop of Wells and lived at the palace. It needed both ingenuity and patience to teach the lesson, but the young lady persevered until the swans learned it so successfully that they have never forgotten it and show no sign of forgetting so long as swans shall sail this moat.

The current pair of swans, Grace and Gabriel, teach each year’s cygnets how to ring the bell before they leave the moat to begin a life of their own.