Scientists have just discovered that the Brazilian free-tailed bat is the fastest flyer in the animal kingdom, achieving short bursts of ground speeds of up to 100 miles (or 160 kilometers) per hour.
Swifts, which can reach speeds of 110 kilometers per hour, are considered the fastest birds in the world at horizontal flight. And peregrine falcons can even reach speeds of up to 300 kilometers per hour when diving. In contrast, due to their wing structure, bats generate greater resistance, and are generally considered slower flyers. But the new findings may upend this scientific train of thought.
The research was conducted by lead author Gary McCracken, a University of Tennessee, Knoxville, professor of ecology and evolutionary biology and one of the world’s leading experts on bats. He was joined by researchers from the Max Planck Institute for Ornithology and the University of Konstanz, both in Germany, and from Boston University and Brown University. Results are published in the journal Royal Society Open Science.
These are bats leaving the Frio Cave. Credit: Gary McCracken
The study was conducted in southwestern Texas using a novel airplane tracking method. The research team captured seven Brazilian free-tailed bats, each weighing 11 to 12 grams, as they emerged from the entrance of the Frio Cave at night. They then attached 0.5-gram radio transmitters to their backs using surgical glue and then let them go once more. Don’t worry. The transmitters were harmless and designed to fall off after two to five days.
Until the new study, the fastest bird records were collected during short flight segments using tracking radar and high-speed video. McCracken and his collaborators instead used an airplane to follow the complete flight track of the bats.
The resulting models indicate that tail winds did not assist the bats’ flight speed at all. They observed that the bats did exactly what airplanes and birds do, depending on wind conditions.
“When they have a headwind, they fly faster. When they have a tailwind, they slow up,” he said. “This is exactly what has been demonstrated in other flight machines, from airplanes to birds.”
The study results suggest a re-evaluation of the performance abilities and capabilities of bats, McCracken said, noting that their flight performance has been underappreciated.