IUCN lists 62 species as near threatened or worse. The collective name for a group of hummingbirds is a charm. Read on for more about these charming birds. Hummingbirds hum, but the sound isn't from their voices. The hum comes from their rapid wing movements — the smaller the hummingbird, the faster the wingbeat.
A hummingbird beats its wings between 10 and 80 times per second during direct flight. During courtship dives, wingbeats reach per second. The males angle their wing and tail feathers during those dives to create trilling noises and gain a female's attention. Hummingbirds can fly not only up and down but sideways and even upside down. They beat their wings in a figure-eight pattern similar to insects, making them the only vertebrates capable of sustained hovering. The average speed of hummingbirds is 26 mph, with a much slower 2 mph used between flowers.
Astonishingly, some males reach speeds of 55 mph or more when diving during courtship. Most hummingbird species migrate and do so alone. Contrary to the urban legend, they don't hitch rides on migrating Canada geese. Rufous hummingbirds migrate the longest distances, flying 4, miles from Mexico to Alaska every year. Flying nonstop for 18 to 20 straight hours, the ruby-throated hummingbird crosses the Gulf of Mexico to reach breeding grounds in the eastern United States.
Climate change is causing widespread shifts in hummingbird migration. If flowers bloom early, before the hummingbirds reach them, then the birds face starvation. Cuba's bee hummingbird is the smallest bird in the world. It is around 2 inches long and weighs less than a dime at only 2 grams. Unsurprisingly, their nests are similarly miniature, around the size of a quarter, while their eggs are the size of coffee beans.
IUCN lists the bee hummingbird as near threatened. Much of its habitat has been converted to agriculture, primarily cattle ranches, and therefore unsuitable for the birds. Males have brighter-colored plumage to attract a mate. They have other adornments as well. The tails of species like the long-tailed sylph Aglaiocercus kingii are so long that the male bird has great difficulty flying.
Only a strong, healthy male comes into a breeding state with a very long tail, and females know it. Female hummingbirds are bigger to allow them to form and lay eggs.
The duller coloring protects her while incubating eggs. Hummingbird nests usually don't exceed the size of a walnut, but they stretch to accommodate growing birds.
The female bird weaves velvety cups from moss, leaves, and fuzzy plant parts like cattail using spider silk. Once the nest is formed, she uses the silk's stickiness to attach lichen and moss to camouflage the nest before laying one to three tiny eggs. The shape suits their preferred nectar source, with some dramatically curved and others very long. To catch insects, the lower half of the bill flexes downward when opened. The fully opened bill then shuts around the insects like a snap trap. That means their feathers and sometimes their whole bodies have no pigment.
Hummingbirds never stop beating their wings, and with their tiny size can look like large bumblebees in the air. They fly in a direct path unless they are making a male display flight. Displaying male ruby-throats fly in a wide arc—about degrees, looking like a half-circle—swinging back and forth as if suspended at the end of a long wire. Their wings make a loud buzz at the bottom of the arc.
Displaying rufous hummers trace a steep U, climbing high, diving steeply, and making whining and popping sounds at the bottom of the dive. Females sometimes join them. They can fly backwards and upside down and to hover. Few other birds can do any of these things, and none as successfully as the hummingbird. By alternating flapping their wings forward and backward, the up and down forces and forward and back forces cancel each other out, so the hummingbird hovers in one place.
How are ruby-throats and rufous hummer different from and similar to other hummingbirds? These two species have wider ranges than other North American species, the ruby-throat predominating in the eastern half of the continent, the rufous in the western half.
I have never seen a Ruby-throated hummingbird on the ground. Do they ever land and if they do, can they wak around? They can hop a little, assisted by their wings. Hummingbird vision is much more discriminating than ours—they can see things at a farther distance, and are able to see a wider spectrum of colors than we can, into the ultraviolet range. They are especially attracted to the color red.
A hummer reacts to sights much more quickly than we can. Hummers can probably not taste as many flavors as we can, though they apparently notice exactly how sweet necar is, and prefer it very sweet. They probably cannot smell as many odors. And they flap their wings really fast—faster than any other bird at up to 70 wingbeats per second. That adds up to more than 4, wingbeats per minute!
In this activity, kids see if they can flap their arms as fast as a hummingbird flaps its wings. All you need is a stopwatch. First, have your child or children hold their arms out like wings. Ask them to practice flapping. See how long they can keep up an easy flapping pace, about one flap per second, before they get tired.
Ask if their arms ache a bit from flapping. They should notice that their outer chest muscles and arm muscles are tired.
Explain that since we walk to get around, our leg muscles are often more fully developed than our chest muscles. Some birds, like turkeys, chickens, ostriches, and other walking birds, also have stronger leg muscles.
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