The cold weather has frozen the local pond and the resident pair of mute swans were a bit put out by the arrival of another pair. Here the resident male is chasing off the interloper.
He flew off, but circled round and landed at the other end of the pond. The local one then laboriously worked its way back down the pond (breaking the ice as he went) to chase him off again - with much the same effect and the incomer back where he started!