This has been fenced off. April 10th Radio Orkney had an item about the protection (they have now also covered it with matting owing to rabbit damage) but don’t say whether still accessible to the public. Fence visible on this pic themodernantiquarian.com/post/128081/great_sacred_monuments_of_stenness.html latest pic, Salt Knowe on the left
I wondered whether "Pesky rabbits" was a reference to our furry friends doing the archaeologilists work for them!
Salt Knowe was fenced off last time I was on Orkney in February, got talking to a Historic Scotland ranger who said that once the anti-bunny matting had been installed the fences would be coming down. I'm back up on Mainland in a couple of weeks so will be interested to see whether that's the case!