World's Fastest Flyer Is a Hummingbird?

Matt Kaplan, National Geographic News 12 Jun 09;

Clocking in at a maximum of 229 feet (70 meters) a second, the peregrine falcon has long reigned supreme as the fastest flying bird in the world.
But if size matters, that title actually belongs to the tiny Anna's hummingbird, new research reveals.

Intrigued by the elaborate, fast-moving courtship dives of male Anna's hummingbirds, Christopher Clark at the University of California, Berkeley, set up high-speed video recorders to get a better look at the action.

"The birds nearly always dive toward the sun, and they have brilliantly iridescent magenta heads," Clark said.

"Because they line themselves up with the light, this maximizes the reflectance off of their heads, and they look like little magenta fireballs falling from the sky."

Those fireballs move at 90 feet (27.3 meters) a second, technically slower than a peregrine falcon, Clark and colleagues report.

But in terms of body size, the hummingbird moves at an average of 385 times his own body length a second—blowing away the falcon's 200 body lengths a second.

As they pull up from their dives, Clark found, the hummingbirds also experience almost ten times the force of gravity, or ten Gs.

By comparison, race cars that accelerate from zero to a hundred miles (160 kilometers) an hour in less than a second subject their drivers to a mere five Gs.

Clark was not expecting such extreme performances from the tiny birds.

"I was surprised, and double checked my methods several times after I got the first measurements, because they seemed really high."

Findings reported this week in the journal Proceedings of the Royal Society B.