The retreating spring tide had exposed a shimmering expanse of flat sand, as if a cloth had been drawn back from a polished wooden table. Across the lightly corrugated plain, pools as shallow as dinner plates were laid out, serving up rich pickings for flocks of gulls. Within these stretches of water, numerous small fish had been stranded – silvery juveniles that one generally lumps together under the term “whitebait”.

One of these finger-length fish stood out from the rest. A striking metallic green along the upper side, it would have looked perfectly at home in a tropical aquarium. It was poorly camouflaged against the sandy bottom, so I scooped it up and released it in a larger pool, where seaweed offered somewhere to hide.

The sands of Westward Ho! beach exposed at low tide. Photograph: Charlie Elder

But when it came to identification, I was at a loss. The suggestions of experts who later viewed my photographs didn’t quite tally, while online sites failed to fill me with confidence.

I believed at first that it might be a young European smelt – a rare find along this stretch of coast. Smelt apparently smell of cucumber – not that I had thought to test this. Its colouring, forked tail and slightly prominent lower jaw were promising. However, a tiny adipose fin characteristic of the species was not visible in my photos. Finally, I plumped for an immature herring. A more likely contender, though – given my lack of expertise – I remain far from certain.

The wider issue that lingered after the encounter was why I felt such a pressing need to identify this attractive tiddler. Was it not enough to simply appreciate its eye‑catching looks? One may marvel at a landscape without being able to name individual mountains, or a starry night sky clueless as to the constellations. Only when it comes to wildlife does every sighting come with the fundamental question: “What is it?”

A lifetime’s worth of nature documentaries and the campaigns of conservation organisations have encouraged us to look and learn in the outdoor classroom, to play the citizen scientist. And I am a dedicated follower of the “I spy” imperative to label, record, share.

Perhaps it can be equally enriching not to know. To simply wonder. I spotted a beautiful green fish in a shoreline pool. That is a pleasure in itself.

Country diary is on Twitter/X at @gdncountrydiary

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