Functional daylight echolocation in highly visual bats

Bats rely on echolocation for operating in dim light or dark conditions. Accordingly, most research on echolocation is performed under dark conditions with a few exceptions. Bat species that emerge to forage before sunset have been shown to use echolocation even in relatively high light levels^1-3. It has been argued that for insectivorous bats, as light levels decrease, echolocation rapidly becomes advantageous over vision for detecting tiny insects during dusk or dawn² and that information from the two sensory modalities is integrated^4,5. Functional use of echolocation in broad daylight in insectivorous bats has been scarcely reported^6,7. Here, we report functional use of echolocation in broad daylight in highly visual fruit bats.