One of the biggest signs that you have bats would be if you find bat droppings along eavestroughs, and on your roof near points of entry. You may also see bat droppings on decks, porches, attic, and windowsills. Sometimes there’s also a smell that accompanies it, and people have described it as an ammonia type smell. It can permeate your walls if left for a long time.
Seeing bats around the house in the morning and evening
Since bats are active mainly at night, you won’t be seeing much during the day. They start their day in the evening, and finish up in the morning. If you’re seeing this, there’s a good chance that the bats may be nesting in your attic or walls.
Bats actually communicate via chirping noises. They’ve got such good echolocation for finding their prey as well as finding their way around obstacles, but they do communicate with each other through chirping. If you’re hearing a lot of noises that resemble chirping at night, dusk or dawn – there’s a really good chance you’ve got bats in the house.
Stains on possible entry and exit points
Something most people don’t know is that bats actually secrete oils and grease on the surface of their skin. So when they’re going in and out of your house by their little entry holes they’ve found or created, you can start to notice stains. They’ll leave a bit of a greasy stain that other rodents like squirrels and raccoons won’t. This is a telltale sign that you’ve most like got a bat infestation and should take care of it as quickly as possible.
Scratching noises in the walls
Bats have really big claws/nails, and when they move around inside your walls you can hear scratching noises. This can be really spooky, so if you’re hearing scurrying or scratching noises in your walls or attic, it could very well be bats or other rodents.