Pest Control Questions Answered

Question:

Help!  I don’t know what I have in my wall, but it is about to drive me nuts.  I have set snap traps, sticky traps, put out rat bait, mouse bait, rat traps, mouse traps, and called two exterminators.  I think the second one is about to cut holes in the sheetrock.  This thing is living in either my wall, or in the attic of my townhouse.  I think it’s in the wall, but sound is hard to place.  It is a multi-family dwelling.  The scratching/chewing noise is at night, it wakes me up about 2 a.m. and continues about every few minutes until about 7 am.  I put rat and mouse bait, pellets and bars, in the only place I saw droppings.  It ate a lot of it and piled it up and put it in under the insulation in a place under the stairwell where there are open studs and insulation.  There were dropping that looked like black elbow macaroni, and sheetrock “chewings”.

Help!  I am about to put my house on the market, and I can’t figure out how to solve this problem.  It’s been going on… I’ve been putting out traps in the attic and in that closet for two months.  Yesterday, the exterminator put about 8 snapper traps outside with peanut butter.
Within the last two years, I have caught two animals I thought were shrews (moles?), in that same closet, and I have caught two mice there too.  I cannot find the entry point and all holes have been sealed as far as I can tell.  Also, I pulled out some of the insulation in that closet and there was a live worm in it.  Two French drains were installed about a month ago, and there is a lot less humidity in the room (this is slab construction) that backs up to that particular closet under the stairwell.  Is it possible this animal lives underground and has decided to move into my wall?  Any advice you can me will be much appreciated!!!

Amy
Greensboro, North Carolina

Answer: Dear Amy--

Although you have mentioned many experiences relating to home invaders, the three points that are most significant are the time of day noises, the storage location under the stairwell where insulation is exposed, and the shape of the droppings.

You are experiencing a rat invader; probably a female that sought a safe place to birth her young.  The time of day, intermittent scratching, and or chewing until 7AM rules out squirrels.  Squirrels will be active until 8PM, and become active again around 6AM.  Also the location of the stored bait plus the quantity of bait consumed does not usually permit squirrels an extended survival.  Rat droppings are shaped like you describe.  Rats will remain active all night long.  They are nocturnal while squirrels are daytime creatures. It sounds as if you are receiving rats via a squeeze through spot in your sewer line. You may have experienced sewer issues in the past.  he fact that you had moisture issues may be a clue.

First, eliminate the existing rat condition which sounds like a small family population.  Secondly, investigate sewer breaks or separations.  This may require a sewer video camera. We'd be glad to respond to future questions.

Good luck and best regards,

George Manning
Entomologist

Chicago Pest Control