When I realized I had a squirrel or possibly his entire family in my walls, I did what every modern person does when they have a problem and need a solution, I Googled 'how to remove squirrels from your attic'. In .24 seconds, I got more than a million results. So, I'm guessing this is a common problem.
If you think of squirrels as cute little furry animals that dart through the trees in your yard with amazing acrobatic grace like I did, then you've never had one in your house. Because once they cross that line of demarcation, once they go from outside to inside, they become evil rodent aliens.
Matching wits with a squirrel that's in your attic will...well, drive you squirrelly. This one is in a section of our house that is inaccessible -- in the walls right next to our bedroom and between the chimney and our built-in bookcase. Squirrel shows up at night just as we're getting ready for bed, and gnaws or scratches. I sit up with my ear to the drywall listening to this, wondering what squirrel could possibly be doing and why. Picture me on one side of the drywall and the squirrel on other. If I had a gun, I would shoot him/her right through the drywall! If I'm a squirrel, I'm lying down and keeping quiet.
The next morning, I call the local animal control place and they give me the name of Brian,the animal guy. "He'll help you", they said. I call Brian. He doesn't handle squirrels, just raccoons, possums, and skunks. But he gives me the name of another guy, Kerry the squirrel guy, and I call him and leave a message.
Meanwhile, I scurry around the house looking to seal up any openings that squirrel might be using to get in. I almost fall off the roof sealing up one opening. That night, I wait, thinking that I got squirrel locked out. Around midnight, I hear squirrel gnawing and scratching in the walls. I think of Bill Murray using dynamite to blow up gophers in Caddyshack. I tell squirrel through the wall that whatever it takes is on the table, including nuclear.
The next morning, I get a neighbor and we replace a roof vent which we think is how squirrel is getting in. Not so, as wire mesh prevents entrance for squirrel. We search the roof for entrances, all corners, everywhere. Finally, we find a vent pipe on the roof that is below the rubber flange which has tell-tale signs of being chewed. We seal it with heavy gauge wire mesh. Squirrels have amazing powers of gnaw. Only metal thwarts them. Now hopefully we didn't seal squirrel and his babies inside.
The next morning, Kerry the squirrel guy returns my call. I give him an update. He seems very interested in my progress. He tells me that squirrels are very territorial, and will fight other squirrels who violate their territory. I wonder why I haven't seen a National Geographic special on this. He warns me that if I trap squirrel, I'll need to take squirrel at least 3-5 miles away to release squirrel. I laugh, imagining squirrel with suitcase hitch-hiking back the 3-5 miles to my walls.
That night, no squirrel noise. The next morning, I look out the window and see a squirrel in the yard. We eye each other contemptuously. I swear he mouthed to me, "Wait 'til next year".