Airplane tracking documents the fastest flight speeds recorded for bats

Area of Science:

• Comparative biomechanics
• Vertebrate flight dynamics
• Animal locomotion

Background:

• Birds are generally considered faster and more efficient flyers than bats.
• Fast-flying bats and birds in open airspace share similar wing shapes and flight dynamics.
• Previous research has underestimated bat flight performance.

Purpose of the Study:

• To investigate the flight behavior and maximum speeds of free-flying Brazilian free-tailed bats (Tadarida brasiliensis).
• To compare bat flight performance with that of birds and other flying animals.
• To re-evaluate the functional differences in flight abilities between bats and birds.

Main Methods:

• Tracking the ground speeds of seven free-flying Brazilian free-tailed bats.
• Utilizing regional wind modeling to analyze flight speed adjustments in response to wind conditions.
• Observing wing beat frequency and identifying flap-gliding strategies.

Main Results:

• Maximum ground speeds achieved by these bats exceeded previously documented speeds for any bat species.
• Bats demonstrated adaptive speed adjustments: flying slower with tailwinds and faster against crosswinds.
• Increased wing beat pauses at higher speeds indicated the use of flap-gliding for rapid flight.

Conclusions:

• Bat flight performance, particularly in species adapted for open airspace, has been significantly underappreciated.
• The study suggests that functional differences in flight capabilities between bats and birds warrant further investigation and re-evaluation.
• Brazilian free-tailed bats exhibit sophisticated flight strategies, including flap-gliding, to achieve high speeds.