I'm no expert but I think, if it is a cat who's 'performing', and they leave their doings on display, it's a sign of dominance. (My Heidi uses a litterbox and always goes round the edges and buries the leavings, she never goes in the middle or leaves it on display.) So, I wonder if your visiting moggy needs to be put in his/her place, ie if you see the cat shoo it away or use a water pistol (not the 'power' type though). Bog-normal black pepper sprinkled round the grass should help, don't know what the grass would make of it but it certrainly deters cats.

Like Ann, I did wonder about foxes. Don't have a clue how to stop them performing though, sorry.

Hope you get something sorted and soon,

Lorna
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