Saturday, 19 July 2014

Touch of the vapours

Excellent newcomers continue to arrive here daily, or rather nightly, in spite of some interesting weather conditions. Massive claps of thunder woke us at 3am on Friday to find the surrounding area blazing white at regular and brief intervals as lightning played all around. Saturday night featured a roof-drumming torrential downpour.

In such circumstances, the Vapourer moth is an appropriate visitor with the somewhat sulphurous ring to its name. It looks potentially like one of Old Nick's crew, don't you think, with that pair of gleaming, closely-set 'eyes'. Try as I might, however, I have yet to track down online a reason for the name 'Vapourer'. My best guess is that it stems from the exceptionally powerful pheromones emitted by the female to attract suitors.

Her need to do this becomes clear if you look at my picture, left, lifted from the Moth Bible, my constant rod and staff. While the male zooms around on his handsome foxy-coloured wings - a good alternative name for the species is Rusty Tussock - his partner is wingless and resembles nothing so much as a fat woodlouse.

And yet she has actually evolved into this state, dispensing with the wings her forebears once had so that she can save her energy for producing eggs. From the human point of view (and the impossible thing I would most like to do is fly under my own power), this seems a definite step back. But evolution is concerned only with reproducing the species, so Miss Vapourer sits comfortably on her tree trunk, turns on the scent glands and whoopee, males come from near and far.

The Vapourer is also interesting for its fantastic caterpillar, which is one of the best-armed against predators and further proof of evolution's power to protect. I've borrowed a picture from Wikipedia to show you its various spines, tussocks and warning colouration. And it's poisonous into the bargain.

The Dusky Sallow, by contrast, sports a beautifully gentle pattern whose tones have all the skilful matching of the flowers on one of William Morris's wallpaper designs. But it's also effective camouflage. Compare, for example, with the Army desert uniforms on the left.

Two other regulars, both here and in Leeds, have also put in their first appearances of 2014: the Copper Underwing (or Svensson's Copper Underwing; hard to tell apart without excessive intrusion) and a Dun-bar, an extremely variable moth. Both chose to snuggle up to udiies; the Copper Underwing choosing a Double Square-spot and the Dun-bar (like the Dusky Sallow) one of those curious tablet-like creatures, Common Footmen.

No comments: