Mice Infestation

We have found wild life in our basement.  We have found both a dead mouse and a dead bird.  We also have a mouse infestation around the outside of our foundation.  You can see their little tunnels all over the sides of the house where the stone meets the ground.  We got alarmed when we started to find dead animals in our basement.

We mentioned this to the PM who had two of his guys fix a few other small items on the house.  Both walked the outside and one walked the inside and could not find a hole.  He said he could not find a hole and since the basement ceiling has drywall on it, he couldn't see anything.

Well........

I have been slowly working on building out the basement.  I have been framing walls and trying to get ready to do a rough in with electrical.  While I was removing drywall to run wiring, I found a hole in the foundation for the AC compressor that was not filled in.  Considering it is sealed to the vinyl siding with a flexable sealant, the mice getting in must somehow be crawling under the vinyl and into the hole I discovered.

Here is what it looks like:

I plan to spray foam it full of expansion foam and stop a potential entry point to the house for the mice.