Friday, 3 October 2008

Up in the air


I finally managed to achieve a summer-long ambition last night: hoicking the trap up on to a balcony for a (relatively) high-altitude survey. We made a screen of old towels to protect our kindly neighbours, but alas I'd left it too late. The night was cold and I switched the light off at 11.30pm because rain was forecast, although in the event it hasn't come. The result was a mere two moths. It wasn't a complete waste of time, though, because this one, our old friend the Green Carpet, behaved in a way which increases my interest in how and why moths react to light. Disturbed as I bumbled indoors clutching the trap, it flew fast and drunkenly round in circles, before collapsing on to a pile of books. It tried several times but was far too disorientated to escape. This seems to bear out suggestions that moths are not so much attracted to bright light as confused by it. I shall try to find out more next year. As patient, regular readers will know, I am specially fond of the colour green in moths, so here is another picture with the colour enhanced(ish) by flash. If you double click on it, you will see that the moth's tail, held upwards in that distinctive way, looks exactly like an old-fashioned shaving brush. PS Note Martin Harvey's kind and helpful Comment. This is a Red-Green Carpet, rather than a Green one. Sorry.

2 comments:

kitenet said...

Some years ago I experiemnted with hauling moth traps up into trees on a length of rope. I never managed to get them very high, but was hoping to find some difference between the catch at ground level and the cathc in the canopy. Couldn't find any noticeable effect, although I didn't do it in a consistent enough way to do any proper analysis.

Pedantry from a moth-geek: I think it's a Red-green Carpet rather than a Green Carpet.

Martin

MartinWainwright said...

Oh sorry about the identification - if you have plenty of time and scroll through this blog, you will find other examples... I'll change it.
Have you read the passage in Ford's 'Moths' where he and a colleague go up in a balloon courtesy of the RAF? It's very funny. They had a good time but didn't see many moths (though enough to make them think it was worth trying something on a larger scale. I don't know if they or their successors ever did).