November 12, 2009
Strange BiologyHummingbird's Flight Speed Beats a Fighter Jet
A male Anna's hummingbird is distinguished by a ruby red patch on its chin and head. (Photo credit: Tim Zurowski/All Canada Photos/Alamy)
Male Anna’s hummingbirds (Calypte anna) have quite an impressive courtship display to impress the ladies. When the male spies a female during the breeding season, it proceeds to soar 30 meters up into the sky and then dives down toward the female, reaching speeds up to 27.3 meters per second (61 mph) at the peak of its dive. As the male hummingbird pulls out of the dive by outstretching its wings, it experiences forces more than nine times the force of gravity. As the study’s author points out, these same G forces would cause a trained fighter pilot to black out due to a rush of blood away from the brain. Luckily, the G forces do not have the same affect on the diving Anna’s hummingbird.
In studying the hummingbird’s nose-diving courtship behavior, Christopher Clark, a Ph.D. student at the University of California-Berkeley, enticed males by setting out a caged or stuffed female Anna’s hummingbird in an area where the male could see it. Clark then placed a video camera in the area to capture the male’s flight. In addition to a standard video camera, Clark also used a video camera capable of capturing 500 frames per second.
Clark’s set-up was successful in garnering the interest of male Anna’s hummingbirds. More interested males flew up and dived by the female for a total of 10 to 15 times in a row. One overzealous suitor made 75 consecutive dives, taking only a few minutes’ break.
In recording the hummingbird’s diving activity, Clark observed that the birds flap their wings when first diving, then fold their wings close to their body as they bullet down straight toward the female. The birds outstretch their wings at the base of their dive, heading back upward to make another pass.
In addition to their amazing speed, Clark determined that the hummingbirds also travel at a rate of 385 body-lengths per second. This figure is faster than a peregrine falcon (200 body-lengths per second), fighter jet (150 body-lengths per second), and space shuttle re-entering the atmosphere (207 body-lengths per second). Using this data, Clark concluded that the male Anna’s hummingbird has the “highest known length-specific velocity attained by any vertebrate.”
The results of Clark’s research were published in the June 9, 2009 edition of the British journal Proceedings of the Royal Society B.