I love walking beneath the Scots pines where the rooks nest. A busy road runs close by, but when you pass under the trees you’re lifted up and immersed in the sound-world of these glossy, purple-black members of the crow family. This morning, before catching my train, I stood beneath the pines for half an hour just listening. Rooks are highly talkative, and I could hear not only the famous, raucous “craaa”, one of my favourite noises of early spring, but also, during gaps in the traffic, a far quieter, curiously gentle, click-clacking sound, almost like the kind of gurgling humans might make to a baby.