Facts on the Ruby-Throated Hummingbird

A ruby-throated hummingbird.

The ruby-throated hummingbird (Archilochus colubris) is a tiny member of the species, measuring only 3 to 4 inches long. In "The Encyclopedia of North American Birds," John Terres notes that it is the only hummingbird that nests east of the Mississippi River. During the summer, it can be found over the eastern two-thirds of the United States from southern Canada to Florida, and as far west as the Great Plains. Reaching impressive speeds of flight and wing beats per second, the tiny creatures also migrate over incredible distances.

Appearance and Identification

A male ruby-throated hummingbird.

Only male adult ruby-throated hummingbirds have a vivid red gorget, or throat feathers, topped by a black chinstrap. Both the adult male and female present emerald-green iridescent back feathers and pale gray or whitish feathers below. The male has a pronounced fork in his tail, while the female has a rounded tail shape. While both sexes of immature birds resemble the adult female, immature males have more pronounced markings on the gorget, which Sheri Williamson's "Hummingbirds of North America" calls a "five o'clock shadow."

Mating

A female ruby-throated hummingbird.

Ruby-throated hummingbirds do not form lasting pairs and "The Sibley Guide to Bird Life and Behavior" notes that males mate with "as many females as possible." To attract a female, males show off with a "dive display" creating a U-shaped arc that can begin as high as 40 to 50 feet in the air. Females build nests from plant material and animal hair and bind them with spider webs. They may also camouflage the nest with other materials such as lichen or bark. Typically, females nest 2 or 3 times a season, usually laying two white eggs, which take approximately 16 days to hatch.

Feeding

Ruby-throated hummingbirds feed on nectar.

Ruby-throated hummingbirds are attracted to the color red, and feed on nectar from flowers such as columbines, salvias, coral honeysuckle, bee balm and jewelweed, among others. They also feed on insects. In fact, "The Sibley Guide to Bird Life and Behavior" noted that the tiny birds have been observed "taking as many as 30 insects in one hovering frenzy."

Migration

Ruby-throated hummingbirds migrate across the Gulf of Mexico.

Ruby-throated hummingbirds migrate each fall and spring. Remarkably, they typically make the 500-mile trip across the Gulf of Mexico without stopping! Esther Quesada Tyrrell's "Hummingbirds: Their Life and Behavior" reveals that in preparation for their journey the birds add 40 to 50 percent of extra fat to their bodies to help them survive. Even more incredible, Terres notes, they make the voyage solo, with males departing before females.

Other Interesting Facts

Hummingbirds are fast.

Male ruby-throated hummingbirds have a shorter lifespan than females. Williamson suggests that this may be due to the male's smaller size "combined with stress of territorial defense and migration."

Massachusetts Institute of Technology research, cited in Terres' book, showed that a hovering ruby-throated hummingbird can beat its wings 61 times per second when backing up and 75 times per second when flying forward.

Terres also reveals that in a wind tunnel experiment, a ruby-throated hummingbird was clocked flying 27 mph.

References

• "The Audubon Society Encyclopedia of North American Birds"; John K. Terres; 1980
• "Hummingbirds of North America"; Sheri L. Williamson; 2001
• "The Sibley Guide to Bird Life and Behavior"; National Audubon Society; 2001
• "Hummingbirds: Their Life & Behavior"; Esther Quesada Tyrrell; 1985