Caterpillars and nettles

A day of two parts. The new oven was delivered yesterday so N installed it today and I used it while cooking tea tonight.....so far, so good.
It was an interesting day for wildlife. First of all, I spotted a few large tadpoles in the pond and I tried my best to photograph one. (Extra) No sign of legs yet but they are turning into a good frog colour. I also had a fleeting glimpse of a newt and the larvae of a Great Diving Beetle which I have seen in our pond on several occasions. These larvae are fiercely carnivorous and are probably responsible for the demise of most of our frog spawn and tadpoles during the past three months.
However, the highlight of my wildlife afternoon was this tangled mass of caterpillars. These were on a patch of nettles so I wonder if they are Peacock butterfly larvae. Maybe someone more knowledgable than I can confirm (or otherwise).