The nights of 12th, 13th and 14th October were moth night 2017. You may think that dates so late in the season may not be great for moths, however there is still a surprising amount of diversity on the wing, including scarce migrants.
I put my MV light trap out on the Friday night, and I too was actually quite sceptical about catching many moths. Although my garden regularly attracts upwards of 200 moths a night during the summer months, it is far less reliable in the autumn and winter compared to other sites, for an unknown reason. However, I was in for a pleasant surprise.
Checking the trap at 7am, I could instantly see that it was much busier than I was expecting. The wall of the house near the trap was carpeted with Red-green Carpet moths, one of the most attractive Geometrid moths (the carpets, pugs and waves). There was a Snout moth on the white sheet beneath the trap, a Black Rustic in a gap between the patio tiles, and within the trap itself was my number one target: a Merveille du Jour.
Whoever named the Merveille du Jour (translated from French as Marvel of the Day) was not over-exaggerating. This species is often regarded as the holy grail of autumn moth-trapping; its exquisitely detailed markings and colouration are hard to resist. I’ve only caught one previously, so I was ecstatic about this!
Another highlight was a Barred Sallow moth, one of those species where you can easily tell what it is supposed to be camouflaged as. It has patches of russety-brown and warm yellow, that perfectly match the colours of autumn Birch leaves. It’s certainly an effective disguise, which must have taken millennia to perfect.
To finish off this blog post, I will leave you with a video of the Merveille du Jour. In the video, you can see that it is vibrating its wings. As moths are nocturnal, they cannot get direct energy from the sun (although they do get indirect energy from the plants that they eat), so they have to shiver (like humans do) to warm up their flight muscles. I used a lower shutter speed for this video, which appears to slow the vibrations down and they are shown as a ripple through the wings.
If you are viewing the email version of this blog post, the video may not show, so I would recommend visiting the site directly to watch it.
Don’t worry – all moths were released unharmed!