We have 4 beautiful red corn snakes we caught in our yard and now keep as pets. So we also maintain a Mouse Ranch, a couple of tanks I keep in the barn where we raise mice to feed to our pet snakes. They're tall 20 gallon tanks with home-made tops to keep the mice in. All I had was plastic screening to cover the tops, which the mice have chewed holes through in a few places during a few escape attempts. I've been meaning to get some fine metal mesh to use to replace that plastic screen, but haven't yet gotten the time nor the materials. But as long as the mice have enough food & water they don't try to escape out the holes in the tops. Yesterday morning I went over for a routine check on the Mouse Ranch and was surprised to find... ...a large yellow rat snake INSIDE one of the tanks, happily slurping down the mice! He must have thought he'd found a fantastic snake restaurant! He was clever to have found his way through the extra boards & barricades I've stacked on top of those tanks to prevent mouse escapes, and found the little holes in the mesh to crawl through. I don't know how long he's been visiting the Ranch, there have been other mysterious mouse losses, I thought they had escaped out or had eaten each other. I got him out and took him to a local nature center to try his luck with wild fare again.