All this year I have noticed little piles of earth and sand next to the paths and patio in my garden. It was only after one of the large plastic filter chambers for my Koi pond that sits on a paving slab suddenly developed a significant list that I looked under some of the slabs. I found a very elaborate network of tunnels. I have called the council and they put some poison in the tunnels but they didn't think the tunnels were caused by rats, the tunnels weren't big enough and thought that it must be mice. All I can say is that they must be some big mice. The tunnels must be about 2 ins diameter. What ever the animals are, they have left the bait and redug the filled in tunnels. I tried flooding them out with a hose pipe and they have redug the tunnels. I have borrowed a humane trap and baited it with a sausage, recommended apparently but haven't caught anything yet. Has anybody else had this sort of problem and any idea what is causing it. The amount of earth being excavated is quite incredible and the soil in my garden is very, very stony. I have three cats and they haven't caught anything either.
Kevin