Bats are an elusive species. Cloaked in darkness, they spend much of their time flying at night, feeding on insects. They are known to squeeze into the smallest openings, much like mice, and this makes them extremely difficult to defend against.
Bats will find small holes and gaps near the roofline of your home to gain entry. This photo is an example of a homeowner that was experiencing a bat infestation, and decided to take matters into his own hands. The bags that are draped across the front of his house are meant to act as a one-way-door mechanism, whereby the bats would find their way out of the attic and not be able to get back in.
Unfortunately (but not surprisingly), this didn’t work. All the duct tape and plastic sheeting in the world will not prevent bats from entering a home. Besides being an eye-sore, it’s an ineffective method and not a great DIY job.
Always consult a professional company when faced with bats or other wildlife on your property.