Echolocating bats inspect and discriminate landmark features to guide navigation.

Area of Science:

• Animal Behavior
• Sensory Ecology
• Bioacoustics

Background:

• Landmark-guided navigation is crucial for animal way-finding.
• How animals gather sensory data to distinguish landmark features remains understudied, especially in active sensing species.

Purpose of the Study:

• To investigate how echolocating bats discriminate acoustic landmark features for navigation.
• To determine the reliance of bats on landmarks for successful way-finding.

Main Methods:

• Four big brown bats (Eptesicus fuscus) were trained to navigate through a net opening using an acoustic landmark.
• Experimental and probe trials manipulated landmark and distractor object locations to assess navigation reliance.
• Vocalizations and flight paths were recorded using ultrasound microphones and motion-capture cameras.

Main Results:

• Bats successfully learned to use acoustic landmarks for navigation.
• Probe trials showed increased task completion time and net crashes when landmark cues were altered, confirming landmark reliance.
• Acoustic distinctiveness of landmarks influenced bat performance and sonar inspection behaviors.

Conclusions:

• Echolocating bats primarily rely on acoustic landmarks for navigation.
• Bats exhibit differential sonar attention to landmarks versus distractors, indicated by vocal behavior changes.
• This study highlights the importance of sensory information processing in active sensing navigation.