Sunday, July 7, 2013

Search for the Isle of Wight Wave

Over the last decade I have been fascinated by the search for the elusive Ivory-billed Woodpecker in the forests of the south-eastern United States. There have been tantalising sightings suggesting the bird might remain at large, but many are skeptical, believing it to have become extinct.

Yesterday evening myself, 2 Ians, Rob & Ashley engaged in a search for a creature that is not quite so famous: the Isle of Wight Wave (Idaea humiliata). The Isle of Wight Wave used to inhabit at least one vegetation-covered ledge on the chalk cliffs below Tennyson Down on the Isle of Wight before the ledge fell into the sea in 1931 and it wasn't seen again. It's still found on the continent, this photo coming from a German website with a series of images here:
It's a really small moth with that distinctive reddish streak along the leading edge of the wings.

We've talked about an evening searching for the Isle of Wight Wave for a few years now but, this year, Rob & Ian made it happen, working closely with the National Trust and the Coastguard.

Having examined the images on Google Maps, we set ourselves up on the cliff top above the location of two well-vegetated areas. The main kit consisted of 4 bright LED lights suspended over the cliff face on an extendable fishing road with a Mercury Vapour bulb trap set back from the cliff. The idea was (and this was Ian's idea and set-up) that any moths on the ledges would be drawn to the light from the LEDs and then be attracted across to the main MV light where we were sitting safely well back from the cliff edge.
The Isle of Wight Wave is noted for appearing at dusk and so we set up nice and early, ringing the Coastguard to let them know when the MV light was started up - in the photo above you can see the MV trap and the LED lights connected to the end of the long fishing road. Yours truly is also looking very hopeful there, net in hand and ready to go!

During the evening we encountered a number of fascinating moths, including this Cream-spot Tiger which looks a bit jaundiced in the light from the mercury vapour lamp. There were high numbers of Small Elephant Hawkmoths, together with a couple of Elephant Hawkmoths and a Privet Hawkmoth. Other moths included the scarce Dew Moth and a number of The Shears, good numbers of which flitted around the LEDs before heading towards the MV trap, a sign that the set-up was working.

One of the things that really excited me was the large numbers of Hoverflies that began to appear as soon as the trap was turned on:

The majority seemed to be Syrphus vitripennis, with the Marmalade Hoverfly (Episyrphus balteatus) - both noted migrants - reaching double figures, too. At one point I counted over 50 in sight, and that doesn't take account of any that had settled down behing the egg trays or which may have flown off!

At one point, soon after 11pm, we began to notice the tell-tale, pin-prick lights of lots of Glow Worms in the grass all around us, Wordsworth's famous 'earthbound stars':
I left to cycle back home at 1.30am, having been up since just after 5am the previous morning and having a Service to lead later that day. Rob & Ian stayed behind for the duration. It had been a great evening and there are already plans to continue the great 'Search for the Isle of Wight Wave' in the future.

In conclusion, I'm pleased to report that we actually did get one Isle of Wight Wave, though not exactly the one we were hoping for:


  1. Good to see all you boys enoying yourselves.

  2. It was a great night out! Really enjoying your photos, Peter.

  3. Great to see you are trying to find this long regarded extinct Moth. I have read that the original location was a ledge the local cliffs men called Rosehall Green near the Wedge stone marked on OS Explorer maps.