There are a few different noises that have been shown to scare away bats. These include loud noises such as firecrackers, ultrasonic sounds, and even the sound of someone screeching or making other high-pitched noises. While some of these methods may be more effective than others, it's important to note that no single noise will work for all types of bats. So it's best to try a few different methods to see which one works best in your specific situation.

Different people seem to have different opinions on what noise scares bats away. Some say that it needs to be a high-pitched noise, while others say that anything over 90 decibels will work. There is some anecdotal evidence that suggests playing loud music (especially heavy metal or rock music) near a bat colony will scare the bats away. However, there has been no scientific study to confirm this theory.There are a few commercially available products that promise to get rid of bats, such as electronic bat repellents and ultrasonic bat repellents. However, there is no scientific evidence to support the claim that these products actually work.