I was walking round the edge of the wood when I heard the nuthatch call – the resonant sound of water dripping into a deep well. The nuthatch called again. Louder this time, quicker, more excited.

The little bird had flown into one of the oaks rising above me. But where? Craning my neck, I searched eagerly. I love these birds, their smoky blue backs warmed with apricot underparts, their black “Zorro” masks, their endless journeys through the woodland canopy.