Perhaps this will help?
All bats can see, however bats have developed the use of echolocation to find food when navigating and hunting for food at night. Bats make high-frequency sounds, and the echoes of these sounds bounce back which enables a bat to make a mental map. Using this mental map they are able to avoid the smallest of obstacles whilst locating their prey. In just a split second Echlocation enables bats to determine the size of objects, their location, how fast they are travelling and even their texture! And there are a lot of "old bats" in Turkey