Overnight showers call for an early morning rescue mission along the riverside path, before the trampling rush of people begins. Forefingers and thumbs clasp snails gliding right and lob them into a meadow where reed and sedge warblers sing. Snails tilting their eyestalks to the left are scooped up and dropped on grass beds under the willows. Please don’t break. From the canopy over my stooped shoulders pours the song of blackcaps, garden warblers and chiffchaffs.
Something in this warbler chorus is missing, if names are to be believed. I don’t recall hearing a willow warbler among these copses and spinneys this year or any other, though it is probably Britain’s commonest warbler, and there are hundreds of willow trees here with welcoming boughs. In the south, the sandy lands on which the heath sits seem to be the willow warbler’s favoured nesting domain. Birch warbler might be a better appellation for this bird, for they thrive in the pioneer forests that spring up once the conifer plantations are cleared.
I remember the first of the year at the RSPB reserve one mid-April morning, tuning up at the exact moment that I met a couple walking the other way. “Can you hear that falling song?” I blurted out. “That’s a willow warbler and it’s just arrived from Africa.”
Today I find myself half-running towards the heath, longing to hear the warbler’s dying cadence again, perhaps to sample its melody one last time before songbird spring itself dies away. A French birding website calls the willow warbler’s song inconfondable (unmistakable).
There, out of a lone birch overlooking the open heath, come those first hesitant, stuttering notes, not unlike those of a chaffinch. And then the willow warbler’s USP: a keyboard run descending so quickly in a liquid cascade that the repeated – or near-repeated – notes are lost in what seems like a musical freefall. It sings the phrase over and over, with pauses of a few seconds in between. Repetition does not dull the appetite; each tumbling snatch fades away and I’m left wanting more.
On the new heath, a denser stand of trees, giraffe-ear-high, and one, two, four birds within earshot. Birch warblers.
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