Sonar sound groups and increased terminal buzz duration reflect task complexity in hunting bats

Area of Science:

• Animal Behavior
• Bioacoustics
• Sensory Ecology

Background:

• Difficult tasks often require increased attention.
• Biosonar signals from echolocating bats offer a unique way to study attention.
• Bats use echolocation for navigation and hunting.

Purpose of the Study:

• To investigate the relationship between task difficulty and biosonar signal characteristics in bats.
• To determine if bats alter their echolocation behavior based on prey type and capture method.
• To explore the function of terminal buzzes and sonar sound groups in bat hunting.

Main Methods:

• Monitoring biosonar signals of Daubenton's bats (Myotis daubentonii) during prey capture.
• Comparing buzz duration and the number of sonar sound groups for different prey types (aerial vs. water-borne, stationary vs. revolving).
• Analyzing echolocation data in relation to presumed task difficulty.

Main Results:

• Daubenton's bats produced longer terminal buzzes when aerial-hawking compared to water-trawling.
• Bats captured revolving prey (air- and water-borne) produced more sonar sound groups than when capturing stationary prey.
• Both buzz duration and sonar sound groups varied with prey capture conditions.

Conclusions:

• Terminal buzz duration and the number of sonar sound groups are indicators of task difficulty for bats.
• The terminal buzz may function as an extended sonar sound group during prey attack.
• Biosonar signal analysis provides insights into the cognitive demands of echolocation tasks.