|Rauzon, Mark J. Hummingbirds. Ulster, PA. Grolier. 1997: 12-13.||"Other hummers have been clocked at 200 beats per second"||200 Hz|
|Forshaw, Joseph. Encyclopedia of Birds. New York. Smithmark, 1991: 496.||"The extremely rapid wing beat (22-78 beats per second), coupled with a rotation of the outer hand portion of the wing and a powdered upstroke permits hummingbirds to hover in front of flowers during foraging."||22–78 Hz|
|Chloe, Maria. Chloe's Stuff.||"Small hummingbirds beat their wings 38-78 times a second, larger hummingbirds 18-28 times a second."||38–78 Hz
|Perrins, Christopher. Birds. Tucson, AZ. Readers Digest, 1979: 292.||"In small hummingbirds the rate rises to about 70 beats per second but in the Giant Hummingbird it is surprisingly slow, 8-10 beats per second."||70 Hz
|Schater, Joe and Huegel, Craig. Florida's Hummingbirds.||"The sound is made by their rapid wing movements (50-200 beats per second)."||50–200 Hz|
Hummingbirds are among the smallest birds we know of. Some can be as small as four inches long. They are so small, yet they are so quick. Their quickness helps give them beauty and grace, which is why they are so popular.
Hummingbirds can only be found in the Americas, where we have over 330 species of them. Many of these hummingbirds differ drastically, from their size to their agility. Also, hummers flap their wings at unusual speeds. Sometimes covering more than 200 beats per second. Their wings vibrate on the upstroke and the downstroke which produces a kind of humming sound. The sound varies from species to species as does the frequency. Notably, the larger hummingbirds have less beats per second, meanwhile the smaller and more agile species have recorded up to 200 beats per second.
This amazing feature was also the subject of my project which was to find the frequency of a hummingbird. The results ranged from 18 beats to 200 beats per second, which is a big difference. This difference has to do with the different species and their size.
Mark Levin -- 2000