When he was cleaning gutters, my husband noticed brownish liquid running down the side of the house in one corner. We think we might have squirrels nesting in the attic. Would they have something to do with that?

L.W., Pinardville, NH

Yes, squirrels certainly could be the culprits, especially flying squirrels. When flying squirrels move into an attic, they tend to pick one spot that members of the same squirrel family use as a communal bathroom. That spot is often in a dark corner of the attic in the soffit area. When they fill up one spot, they move over a little bit and establish a new latrine. Because the latrine is in the overhang area of the roof, fecal matter and urine tends to drip down the siding outside.

Facts About Flying Squirrels

1. Flying squirrels are small and can enter your attic through an opening smaller than you would imagine, a crack about the width of your little finger, usually somewhere around your roof line. If the opening isn’t quite large enough, they simply chew it to their specifications.

2. When you have flying squirrels living in your attic, you usually have a bunch – anywhere from 6 to 30 squirrels is normal. If you have more than 6, you might have multiple squirrel families denning there.

3. Flying squirrels are nocturnal so you’re going to hear them running around and exiting and entering the attic at dusk and dawn in winter, and probably all night long in summer. You’ll also hear noises that sound like nuts dropping because those actually are nuts dropping! You may also hear squirrels landing on the roof when they glide from a tree limb.

4. Flying squirrels are expert hoarders and, in fact, the bottom layer of their nest is made up of discarded food material (nuts, pine cones, mouse bones).

Exclusion is the Best Control Method

At Colonial, we have certified nuisance wildlife experts on staff. They can humanely exclude squirrels from your attic and then can “squirrel-proof” your home by sealing openings that the squirrels use to get inside (see Squirrel-proofing Your Home).

For more on flying squirrels, see these Colonial blogs:

• Flying Squirrels Will Den in Attics During the Winter
• How to Keep Flying Squirrels Out of Your Attic
• How Do Flying Squirrels Fly?
• Will Flying Squirrels Feed at Bird Feeders?