An unexpected object on the cliff face

When we went North on Sunday I forgot the SD card reader for my MacBook, and don't know where the one for my my iPad is now.Managed on Sunday by using my phone camera, and then using airdrop to the laptop.Yesterday, it wasn't until I got back from my jog, that I remembered and as I had used my camera, I'm posting Monday's Blip late on Tuesday afternoon.

I would welcome suggestions as to what it is that I saw on the cliff face below our property.