Rarity excites, and focuses attention in the human brain.
It’s crazy really: a Penny Black, a lock of Beethoven’s hair, a 1933 penny, a dodo’s egg, will in their various ways give collectors connection to their secret worlds.
All are useless, except as precious keys to that hole in the wall, where the trapped psyche can struggle through to a mirage of endless place and time.
This so-called adrenalin buzz is experienced by twitchers with the sight of a rare bird.
For me: a dotterel on the sodden ploughed fields of Kent years ago, or the shore lark on the marrams of the Norfolk coast. Butterflies provide me with a buzz too, and this week’s photograph by Brian Henham is no exception.
The brown hairstreak is out right now – if you can ever find one. I am always excited by the glimpses I have in August and September of this elusive fast flyer, which is gone as soon as you see it.
There has been a colony of them in my garden for years. Colony? Well, one or two might just possibly be seen flashing about above the bushes if I am lucky.
They are small; a ten pence piece would cover one easily. They are whirligigs, revolving at high speed round and round on a mad dance like the spiral of a sparkler whirled by an excited child at a birthday party.
Because they are bright orange, this makes them visible even if you are walking and talking.
Provided, that is, you are also looking around you at the scenery, and not at your shoes.
Actually, they are not as rare as a swallowtail or a large copper butterfly; it is just the sighting that is rare.
These in my wild garden breed on a clump of blackthorn bushes left especially for that purpose. These bushes do need pruning every so often to provide fresh young growth on which the caterpillars feed. I have a feeling that last year the pruning was a bit too drastic.
If so, and the hairstreaks have been wiped out, we shall probably never see them again, because these butterflies are stay-at-homes. They never migrate, even for a few dozen yards. Where you will find them best is on blackthorn hedges left to grow along field boundaries. In such places, separate colonies can intermingle and keep the gene pool lively.
If you are lucky enough to have one settle close to you, as Brian did with this one in his picture taken at Pulborough Brooks, you should be able to see the hairstreak down the wing, which resembles a swage-line on car coachwork, or the line on a guardsman’s trousers.
Note also the tail fins, which make this fast flyer look even more rapid, like go-fast stripes on a cad’s car.
Hope you get a buzz as I do if you see one.