We have a pair of resident blackbirds in our garden, and every day the male blackbird perches on the chimney and sings loudly, especially at dusk. He seems to have several ‘songs’ or sequences of phrases which he sings over and over. I’ve heard them hundreds of times, but although I’m a musician and quite good at picking up things by ear, I can never do more than repeat fragments of the blackbird’s song. I certainly can’t whistle the whole song, or even several phrases in a row. They are so intricate, the oscillation between notes is so fast, and the tuning is so … well, so avian, that it baffles my human ear. Many of the pitches seem to fall into the tiny cracks between semitones. I can recognise the shape of phrases and their sequence, but the detail and the precise tuning seem constantly to be just beyond my ability to imitate them.

I can see why some composers have been fascinated by birdsong – famously, of course, Messiaen, whose pieces are full of the cries and calls of exotic birds as notated by him. Perhaps there are some birds whose song can be pinned down in pitches and rhythms familiar to the human ear, but the blackbird’s song would challenge any system of notation that I know about. To write something down, you have to be able to analyse its pitch and rhythm, and our blackbirds have remained serenely inscrutable.