I expect your paving was laid onto sand? Hence the ant movement, clever little insects. Gosh singing that 'dam' song again

(not that you are old enough to remember it ....... )
I measured our nest at the front today: 3ft x 3ft x ........ gave it a poke, lots of orange ants came out

........

I wonder how many years before it over-takes the whole of that border

Why didn't you eat your big fat ripe strawberry Oldsheep? ..........
Annika .......... what other nasties do you have in your plot?