"Need to get rid of squirrels in the attic"
Column #835 02/26/2011
On The Level
Q. We are at our wit’s end and are writing to you with hopes you can help. Our squirrels seem to come in every winter and this year we decided to try to keep them out. We had a rotten piece of wood replaced where we figured they were getting in and out, but the wily critters chewed their way back in and now we have a good sized hole in the fascia right under the roof. We then tried traps to no avail - they are too smart and besides they can get their food outdoors during the day. So now we have contracted with someone to go all around the roof and install metal flashing all around and up under the roof shingles (which probably should have been done during the building) and see if this will keep them out. We are apprehensive, however, that the squirrels will either be trapped inside or, if there are babies inside and the adults are outside, will find a way to chew a hole to get back inside. Any suggestions to insure the squirrels are out?
A. In the years I have written this column this winter seems the worst when it comes to folks telling me about their squirrel problems. My unscientific observation suggests it may have something to do with our colder than normal winter. The basic facts remain the same they just seem to have ramped up somewhat.
Since squirrels don't have a significant natural enemy in the wild, their numbers are controlled by their food supply. A given woodlot will support a certain number of squirrels. So if you remember your school biology, when a species gets to the point of saturation when it comes to food supply, some will try to move on, the weak will die and they will all forage with hunger in their bellies. What throws the equation out of balance somewhat are the kind folks who feed them either directly by throwing things on the lawn for them or through trying to feed birds. As you’ve learned squirrels are masters of getting at bird feeders and feasting while shooing birds away. Inventors spend countless hours devising squirrel defeating bird feeders but it doesn’t take long for squirrels to figure a way around them and still get at the bird food. Thanks to the kind-hearted, squirrels now have an increased food supply so they can have more baby squirrels.
Squirrels look for a suitable spot to build a nest. Frequently that suitable spot is in the warm, insulated attic or framing of a house if they can get in. A determined squirrel can and will chew through most any wood or gypsum product (drywall) to get in and can do so in a hurry. Metal or masonry will slow them to a stop but for years we have used plastic gable vents. When a tree close by grows to the point where a squirrel can jump onto the roof and climb over the roof edge at the gable where the plastic vent is short work for them to gain attic entry. The thin metal screen behind the vent face is for bugs, not rodents.
If a squirrel finds its way in the house and then can’t find the way back out it will become frantic, chew things randomly, become exhausted, dehydrated and die. If that happens you will smell it. An adult squirrel weighs about a pound and half and that will smell for some time. So you need to be sure they are all out of the house before you seal it up with any sort of wire cloth barrier. Climb into the attic and look to see if you can see clear light coming from the gable vent or anywhere else where they might be getting in. Don’t abandon the rat-wire concept even on the outside if you can’t get to the holes seen from inside the attic. It will probably be your best bet. You can paint it to match the house color so it will camouflage itself.
Squirrels in the attic are more than an annoyance. They excrete while up there and after a while that can become a health hazard for anyone who ventures into the attic. Take an ultra-violet light and shine it on the insulation and all the squirrel urine will glow. And it can get worse. As I mentioned these animals spend most of their time foraging for food and while up in your attic will chew on the vinyl covered electrical branch circuit wiring. I have a friend whose house in the Historic District suffered a catastrophic fire that the fire investigators pinned on squirrels gnawing on hot wires.
Forget the mothball trick. Sprinkle some mothballs in the attic and it will keep the squirrels away, I've heard. Not entrirely true. The amount of mothballs you'd need to discourage squirrels from nesting would probably cause you to move. The same friend who had the squirrel started house fire built a gazebo in his back yard and some squirrels decided the cupola top would make a suitable dwelling. He went to Home Depot and found a product called“CritterBeGone” (http://www.critterbgone.com/). It worked for him. It’s an “organic” product and my friend thinks it’s some sort of spice like pepper that drives the squirrels away. I won’t tell him I researched the product and the spice that chases the squirrels away is concentrated fox urine. The squirrels smell what they think is a potential predator and split. I don’t know about using that inside a house.
One option is to go to Anne Arundel County Animal Control located at 411 Maxwell Frye Rd. in Millersville (410-222-8900) and request the use of a trap to catch them. They will tell you how to bait and set it and if you catch one, you call them and they come and remove it. They’ll let you keep the trap for a week but if you have multiple invaders you can ask for an extension of the trap use until the job is done. If you don’t want to deal with them yourself there are several professional animal trappers who’ve been doing this sort of thing for a long time and can take care of these critters for you. Then seal the attic with wire cloth.
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