"I could hear the flight calls of a flock of Greenfinches clearly between the noisy rattles and squeaks of a Starling singing at the top of the Walnut tree. I looked up, expecting to see the flock pass overhead, but the pale blue winter sky was empty. Slightly puzzled, I resumed raking the dead leaves. The calls came again, but still there were no finches in sight. Then I realised that the twittering chorus was part of the assortment of sounds coming from the Starling."