200 Years. 200 Stories. Story
39: “Birds in a Hurry
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Long-tailed Hermit (Phaethornis superciliosus): (Photo by Brian Gratwicke, licensed under Creative Commons Attribution 2.0 Generic)
Birds in a Hurry
Anybody who has watched a hummingbird in flight knows that these amazing birds use a lot of energy. They zip and dart about, and while hovering, their wings can beat 20–25 times per second. Based on an extensive series of engineering studies on bird flight by Crawford H. Greenewalt, hummingbird flight is most efficient at 5.5–7.5 meters/second (or 12–16 mph). If they go any faster or any slower, the birds burn a lot of extra energy.
The Academy’s Dr. Frank B. Gill wanted to find out how fast these birds fly in the wild. In June 1982, he conducted a study of the long-tailed hermit (Phaethornis superciliosus) in the rainforests of Costa Rica. Many hummingbird species are territorial and will defend a patch of flowers, so it’s hard to measure their “normal” flight. But by estimating the time it takes for these birds to fly the 40 meters (131 feet) between two artificial flowers, Gill was able to record an average speed of 11.6 m/second (26 mph), which is nearly double hummingbirds’ most efficient speed!
What is the Academy’s Ornithology Department up to now? Visit ansp.org to find out!