Angle Shades Moth Caterpillar decent

[plunk502]

I saw a caterpillar - light green - which seemed to be descending from an oak tree on a silk thread. I think that it was an Angle Shades moth but have not been able to find this behaviour described elsewhere.
It may have just fallen and broken a spiders web but the descent seemed controlled.
After a while a brownish thin wasp-like fly (ichneumon?) ran down the thread and the caterpillar immediately dropped to the floor. The fly then flew down after it.

[dmclean2]

Hi PLunk 502,
Welcome to WAB
Some caterpillars have this type of lifeline to escape predators, I had a tortrix moth caterpillar do the same thing on a bush in my garden,
The Ichneumon fly, from your description could possibly be Ophion luteus an all brown endoparasitic wasp which lays it's eggs in a variety of caterpillars, When the eggs hatch the grubs eat all the non vital organs first
so I don't hold much hope for your caterpillar,
other Ichneumons lay their eggs on the caterpillars, ( just as bad)
Hope you enjoy the site, and look forward to the day that you can back up your sightings with a photo, that will come in time so have patience and see you arround
Duncan

[plunk502]

Originally Posted by dmclean2

look forward to the day that you can back up your sightings with a photo, that will come in time

... and a camera!

It probably was Ophion luteus

Pete