It’s hard to get famous when all you have done is get lost, but Mark Thatcher managed it and now the white-crowned sparrow has done the same thing. In Canada and in the southern United States, or anywhere in between at migration time, a white-crowned sparrow is nothing much: a mere bit-part player in the continent-wide drama of wildlife.

When it misses its way and turns up in north Norfolk, it becomes a superstar. It’s not a rare bird, because the species is not under any kind of threat: it’s a rare bird in Britain because it’s not supposed to be here. It has somehow absent-mindedly crossed the Atlantic: perhaps it asked directions from a New York taxi driver.

At least it has conformed to some of the greatest traditions in the history of the study of wildlife by attracting the notice of a vicar: in this case, Richard Bending, a retired clergyman who lives in Cley. Cley (rhyming with sly) is a birding mecca: but it’s the soft, marshy seashore that brings in the boys with the telescopes: not, in the main, a vicar’s back garden half a mile from the sea. This is a freak, a curiosity, a one-off. To most bird-watchers, it is nothing more than an amusing tale. To a scientist, a serious ornithologist, it means nothing at all. It is more interesting to a student of the vagaries of stratospheric winds, or for that matter, shipping – the bird may have been blown here, or it may have got shut in a ship’s hold.

But twitchers are not scientists. They are sportsmen, in hard training, and at times like this they are eaten up with the competitive urge. If they see the white-crowned sparrow, their list of British birds goes up. But – and this is even more important – if they fail, other people’s lists will rise at their expense. Hence the feeding frenzy at Cley, which has been the site of a serious invasion of men with terrifyingly expensive optical glass.

Wish them well, for they harm no one and have donated money to the local church in a collection designed to make the most of this strange blessing from the heavens.

Meanwhile, the bird itself is most likely on borrowed time, for most of these windblown wanderers die soon after they have been identified. But this white-crowned sparrow has teamed up with a flock of finches, is using the Bendings’ garden-feeders, and may hang around for a while.

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