Apparently, bats can collide into things too! Oh bummer, poor little creature.
It is known that bats use echolocation to navigate around, to socialize, and to forage for food, all these, in the dark. In natural environment, the emitted sound waves from their nose or mouth, where it will bounce back to them, reflecting what ever obstacles or even prey in front of them.
However, when it comes to glass windows, or any smooth surfaces, bats tend to perceive it as, another things.
It is proven that bats too can mistake smooth vertical surfaces as clear flight paths, repeatedly colliding with them (Greif et al, 2017). From the experiment done by Greif and his colleagues, 19 out of 21 individual bats collided with vertical plate, at least once. Most foliage return some echoes back but smooth surfaces somehow reflect the echo away at incident angle. Bats disable to interpret whether the sound is just travelling away or not, which lead to collision, if there is such sensory traps in front of them. Usually, when they hear nothing in front of them, they won’t produce more calls, and the flight speed won’t be slow down, hence the possible injuries.
These windows and glass surfaces could pose a serious threat to bats given the numbers of new buildings have been built into the bat environment in recent decades, and this explain why injured or dead bats can be found near it. But, how about the other angles? Does a tilt window glass or surfaces have any impact on bats behavior too? It would be interesting to see whether they can deal with this threat and learn to avoid and maneuver around such surfaces so they won’t collide if it is located near their roosting site.
This is one of the aim of this project, to observe bats sensory around most common objects we could found in the cities such as roof, windows, board sign, wall and others.
