2. Grease and dirt buildup

Many pests, including rats, mice, and certain insects, tend to follow familiar routes when lurking in an enclosed area. This sounds very gross, you’re right, but the good news is that this weird behavior of theirs will often leave behind a greasy or sticky residue.

This being said, include this one on the list of signs of a pest infestation. This will help you recognize the alarming signs sooner and act accordingly so the pests don’t do any more damage to your home.

Cockroaches have been observed to leave behind brown marks on certain surfaces, such as walls, especially in kitchens and bathrooms. Rats also often scurry along walls, leaving behind dark grease marks.

When you’re dealing with an infestation in your house, you will often see excess grime or dirt building up, especially in narrow spaces or smaller corners that are easy for those nasty invaders to hide in.