Animals Wildlife 14 Dazzling Facts About Hummingbirds By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated December 03, 2020 Nortondefeis / Wikimedia Commons / CC BY-SA 4.0 Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species Hummingbirds combine vivid colors and amazing flight skills in a tiny body. Most hummingbirds are between 2 and 5 inches long, with even the heaviest hummingbird weighing less than a AA battery. The number of hummingbird species isn't small, though. There are at least 368 species of hummingbirds worldwide, most in South America, where their bright colors blend in with the lush surroundings. 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. 1. Hummingbirds Really Do Hum 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 200 per second. The males angle their wing and tail feathers during those dives to create trilling noises and gain a female's attention. 2. They Can Hover 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. 3. Many Species Migrate 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 4,000 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. 4. The Smallest Bird Is a Hummingbird Charles J Sharp / Wikimedia Commons / CC BY 2.0 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. 5. Males Are Smaller and Brighter Colored Andy Morffew / Flickr / CC BY 2.0 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. 6. Their Nests Stretch Yerandy1990 / Wikimedia Commons / CC BY-SA 3.0 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. 7. Their Bill Shape Dictates Diet Hal Beral / Getty Images One of the hummingbird’s hallmarks is its long, narrow bill that's specialized to fit into tubular flowers. 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. The sword-billed hummingbird is the only bird with a bill longer than its body. 8. They Eat Every 10 Minutes To keep the fastest metabolism in the world fueled, hummingbirds need a prodigious amount of food. They eat half their body weight in sugar daily through meals every 10-15 minutes. They also eat tree sap and insects. A hummingbird can eat hundreds of fruit flies each day. If an average-sized man had a hummingbird's metabolism, he'd need to eat 285 pounds of meat a day. 9. Their Tongues Coil in Their Mouth Hummingbirds' tongues are as long as their bill and coil to fit in their mouth. The tongue is split and has fine hairs called lamellae. Once inside the flower, the tongue separates, and the lamellae curl inward. The bird flicks its tongue at speeds up to 17 licks per second. This curling and fast licking create a micropump that traps the nectar on the tongue. 10. They Have Big Brains One study found that the hummingbird’s hippocampus is significantly larger, relative to telencephalic volume, than any bird examined to date. Why? Because they need to know which flowers they visited to collect nectar. Hummingbirds remember the quantity and quality of nectar, when they visited the flower, and where it is located. This allows them to feed efficiently. 11. They Don't Walk or Hop Hummingbirds' feet are so small that they only use them for perching, scratching, and nest building. Instead of using their feet to launch into flight, the wings do all the work. Their order name, Apodiformes, meaning footless, makes sense when seeing a hummingbird in flight. Their feet are nearly invisible. While they do have feet, they do not have knees. 12. They Have Extraordinary Vision Hummingbirds see many colors that are invisible to humans due to an additional cone in their eye. This gives them the ability to see UV wavelengths and nonspectral colors. Researchers testing this vision said that the UV+green looked the same as the green without UV to them, but not to the birds. They use this vision to locate nectar, navigate, and judge mates. 13. They Have a Third Set of Eyelids William Freebilly photography / 500px / Getty Images Hummingbirds protect their extraordinary vision with adaptations that keep wind, dust, and pollen out of their eyes. First, they have a third set of eyelids called nictitating membranes. These mostly transparent membranes are drawn horizontally across the eye during flight. Additionally, they have short, bristly feathers around the eyes that look like eyelashes. These feathers, called orbital feathers, act like eyelashes and keep foreign objects out of the eye. 14. Some Species Are at Risk of Extinction Habitat destruction is the primary threat to hummingbirds. Because hummingbirds have such intense nutritional needs, large-scale pesticide and herbicide use and loss of native plants lead to starvation. Demand for tropical hardwoods has led to the clearcutting of the rainforests hummingbirds call home. Habitat destruction is also driven by using the land for cash crops, cattle ranching, mining, and illegal drug cultivation. Save the Hummingbirds Avoid choosing exotic hardwoods like purpleheart and Brazilian cherry from South America.Eliminate pesticides.Attract fruit flies near hummingbird feeders by hanging a basket with banana peels or overripe fruit.Join the Audubon Hummingbirds at Home citizen science project.