When I say the wader roost on the Wash at this RSPB reserve is one of the greatest sights in British nature, it understates one of its central elements: the everyday ordinariness of it. After all, it unfolds once every 12 hours throughout autumn and winter. Go for half a day and you couldn’t fail to have an encounter.

Each visit is also different. Some friends have been to photograph it on hundreds of occasions, and still they return. It can occasionally be quite flat – the birds, perhaps 250,000 of them, follow the tide’s incoming and outgoing, but only slowly, sub‑flock by sub-flock; no alarm, no drama or sudden movement, and little adrenaline. Usually, however, it is unforgettable.

‘There were thousands of knots inland from where we stood.’ Photograph: Mark Cocker

This time it wasn’t the sight of all those fellow creatures that moved me. Rather, it was their sounds I tracked, and I could have closed my eyes and been just as affected. I should add further that on this visit there was none of what I’d seen two days previously: then it was mainly knots and godwits, from the northernmost rim of our planet, twisting and converging like a balled fist as peregrine and merlin made forays at the tide edge.

Instead, there were thousands of knots inland from where we stood, and they came over us as they went back to the freshly exposed mud. The movements were episodic, a few thousand at a time, one to two metres above head height. Knots have long, pointed wings; their flight action is intense, high-paced, direct; and those pipe-like formations assailed us with that thrumming music of wind through tightly hauled canvas.

Blended with it were the sounds of oystercatchers, a metal-on-stone clanging as they flew away in pied chains back to the Wash; then the curlew calls, bell-clear and looping in shape, rose above percussive piping from a whimbrel flock, all against the muted whickering of godwits further off. There were also some dry, squirted notes from skylarks overhead. At one moment, in a lull among this salty Stravinsky-esque birdstorm, there was a solitary linnet, whose high, liquid notes were isolated in pitch and place, and which seemed to bathe us for just a second in unexpected sweetness.