Local Walk

Was going " Stir Crazy " working from home and staring at the same 4 walls so I decided some fresh air was needed and went for a walk down the valley then up to the " Giant's Tooth " and across the mountains back to Mountain Ash.
Not a lot seen in the valley itself Great Tits feeding young out of the nest, Blackcaps everywhere and the other usual suspects.
The climb up saw lots of Chiffchaffs, Willow Warblers and more Blackcaps until I got to the small pine plantation just above " Giant's Tooth " where there were a family party of Great Spotted Woodpecker.
I then turned north back towards Mountain Ash through the meadow type landscape which produced the usual Skylarks and Meadow Pipits.  Also lots of Small Heaths and a Fritillary flew through but too quickly to get anything on it. At the top of this section was a cracking male Stonechat with some young in attendance, Tree Pipit with food in it's mouth but surprisingly for this area I couldn't find any Wheatear.
I then dropped down slightly and walked across the top of the farm towards the forestry where I picked up a year tick in Garden Warbler, I have to get out more lol.
Lots of Chaffinch in the forestry and surprisingly lots of Blackbirds on the forestry floor where to me there didn't seem any life or growth.
Back out into the open above Newtown I decided to drop down by the side of the farm and come out by the edge of Newtown Quarry. This proved quite difficult as everywhere was overgrown, luckily I can remember where most of the paths are from playing here as a child ( why can't I remember what I did yesterday ).  An heart attack nearly occured when I nearly stepped on something which I think was a Weasel or Stoat, I don't know who moved the quickest. Whatever it was it went into hiding I could not re-locate it.
Just above Newtown I then did a good impression of Mr Bevan in Portland and went a**e over tip and then 5 yards further on just to prove it wasn't a fluke I did it again this time on some wire netting stopping rock falls, ouch.

Since I know next to nothing about Caterpillars, that's wrong I actually know nothing about them can someone please tell me what species is in the photo