My concrete patio extends 12 ft out from back of house. Something has dug a tunnel under the patio on both sides where the patio touches the house. It happened last summer but seems worse this year. I don't see any holes in the yard. One of my little terriers is going crazy and today I came home from work to find that she had dug a hole against the patio in an effort to get to whatever is under there. The patio is cracked in the middle and the dog is also sniffing and crying at the crack and trying to dig out the cracked pieces of concrete. I ave never seen this creature and it seems like it does its damage at night. What is it and how do I get rid of it? Do I need to have the on create removed?

Several animals come to mind: woodchuck, chipmunk, mole. Can you take some pictures and put a ruler next to the hole so that I can get an idea of how large the entrance is that it has dug? Photos can be sent to me at: lkammin@illinois.edu