LAS VEGAS (FOX5) — The Nevada Department of Wildlife led members of the public on a “bat walk” earlier this month to spot the flying mammals and learn about their role in the desert ecosystem. Lauren MacLeod, wildlife education coordinator with the Nevada Department of Wildlife, used an echometer to detect bats as they emerged at dusk. The device picks up echolocation calls that bats use to navigate and find insect prey at frequencies above human hearing.