Hummingbirds can hardly be described without the liberal use of superlatives: the largest flight muscles, the biggest brain, the fastest wingbeat, the most rapid heartbeat, the highest body temperature, the greatest appetite and thirst. Hummingbirds are incredible athletes. The ruby-throated hummingbird, for example, migrates more than 1,850 miles (2,977 km) from Nova Scotia, Canada, to Central America, flying between 55 to 60 mph (89 to 97 km/h).
Hummingbirds are unique to the New World. European explorers were astounded by the tiny glittering creatures that zipped up and down, backwards and sideways, with wings humming and blurred. Hummingbirds, America’s smallest birds, are sort of miniature helicopters.
They can soar, or hover for a few seconds, and even fly upside down. In a blur of iridescent greens, purples, or reds, a hummingbird can speed by in forward flight, then brake in midair to probe its needle-like beak into a flower for a sip of nectar.
Its wings beating so fast that they resemble gossamer, the bird will back out of the flower and sidle over to the next blossom. The wings of these adroit little birds rotate rapidly at the shoulder, tilting to force air forward and down on the downstroke, but also backward and down on what should be the upstroke.
Their powerful breast muscle is proportionally four times larger than that of a chicken, and their metabolism is 10 times faster than that of a human sprinter. Some hummers can beat their wings 1,000 times in the span required to read this sentence. In flight, a hummingbird beats its wings about 53 times per second when moving forward. A hummingbird’s heart beats almost 10 times per second during activity.
Hummingbirds have a lot of enemies in the animal world. Small raptors like American kestrel, Merlins, Sharp-shinned hawk, and Jays capture hummingbirds when they rest on a tree branch with their eyes shut. Some of the larger members of the flycatcher family are even able to catch hummers in flight.
Tanagers have been seen catching and eating hummingbirds, and small owls can find sleeping hummingbirds at night. Hummers get sometimes caught in spider webs as they collect bits of webbings to glue their nesting material together. Frog attacks against hummingbirds may be more common than is suspected.
Distribution & Habitat
About some 20 species of hummingbird have been sighted in the United States. The Black-chinned Hummingbird (Archilochus alexandri) prefers dry scrub, woodlands near streams, wooded canyons, mountain meadows and gardens. Favorite flowers include ocotillo, desert honeysuckle, and tree tobacco.
The black-chinned hummingbird is widespread as a breeding species in the Western United States. After the nesting season, most members of this species migrate south into Mexico, although some individuals spend the winter months along the Gulf Coast and in Florida.
The Rufous Hummingbird (Selasphorus rufus) flies farther north than any other hummingbird. As the birds move south toward Mexico (mainly in July and August), they may be found as high in the mountains as 13,200 feet. Hummingbirds are generally feisty, but this species is particularly pugnacious.
Yet at times Rufous Hummingbirds appear to breed in colonies, with some pairs nesting only a few feet from one another. The similar-looking Allen’s Hummingbird (Selasphorus sasin), which occurs along the West Coast from Oregon south, has a green back and cap. The adult male is unmistakable with its rusty back. Both male and female rufous hummingbirds give rather a mechanical-sounding “cbp, cbp, cbp” while they’re feeding or when another bird enters their territory.
The Anna’s Hummingbird (Calypte anna ) has a long bill, iridescent dark red crown and throat (male); white-tipped tail (female). It prefers open woodlands and gardens. When the female Anna’s Hummingbird lays her eggs, the nest may be only half-finished; she completes it while incubating.
Like most hummingbird nests, it consists of tiny stems and plant down, held together and lashed to a branch with spider silk and often camouflaged with bits of lichen. A female feeds her young without any help from her mate. She collects nectar, tree sap, insects, and spiders, and delivers the meal by thrusting her long bill deep down the nestlings’ throats.