Three curlews flush up from the path in front of me. I catch a flash of white, mottled brown, curved bills, but keep on walking. They often wait for the tide to retreat on this patch of coastal grassland close to the mudflats they like to feed on. The mud is submerged now, water stretched over like a second skin.

Another group rises from the ground behind the brambles: four, five, six. Then another, and another, until there are 20 in the air. I keep walking. Like the curlews, I am watching the tide. I am not waiting for its retreat but rather to catch it at its tipping point, when the water becomes safe enough to swim in but still rough enough that I can catch the force of the waves and feel, for a moment, swept up.

A whoosh of wing stops me as another group takes flight. At first, it seems like clouds of curlews lifting and soaring together, but then the starlings start to differentiate themselves – smaller, darker bodies among white bellies and long bills. Starlings glitter through the curlews’ light feathers. Curlews glide through the starlings’ tremors.

Next, it is the sound that separates them. The long creak of the curlew’s cry is like a bow being drawn over a string – a cello, perhaps, out here on the rough grassland – cutting through the starlings’ chatter, until it feels like the bow no longer moves over strings but starlings, as the sound turns to a prolonged trembling that matches their sway. I stand still inside the music. I forget the tide. I forget the waves. I do not need water to be carried away.

Curlews are facing such large declines in breeding populations and ranges in the UK that this gathering, though comparatively small, feels like an abundance. As I stand, enveloped by the throng, I ask: what did I do to deserve the curlews? It is a question that hangs in the air for a moment, caught among the pulsing bodies before one final surge carries it away.

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