I’ve made up my mind. The willow warbler has the finest song of any bird in the world. Walking along the woodland edge, under the bluest of skies, I heard one in the young alders – a shimmering call travelling through the new leaves, tender as a gentle breeze. I listened for half an hour.

The willow warbler showed no sign of tiring. The dying fall of his song is repeated six or seven times a minute; and each time, it descends a whole octave, in a cadence of gentleness, compassion, and a little sadness.