Hungry ruby-throated hummingbirds migrate through Houston on the way to breeding grounds
Resplendent rubythroated hummingbirds hanging around our neighborhoods last September are returning from their winter homes south of the border from Mexico to Costa Rica.
Except this time, they won’t loiter in our yards. They’ll instead be in a hurry to reach breeding homes from East Texas and throughout the eastern half of the U.S. That doesn’t mean we won’t see the tiny hummers, because they must pause to eat after an exhausting 600-mile flight over the Gulf of Mexico from Mexico’s Yucatán Peninsula.
The implausibly energetic hummers will require urgent nourishment when they arrive this spring. They’ll zip into our yards to fatten up on insects while invigorating their high-speed wingbeats from nectar-rich spring flowers and sugar water in hummingbird feeders.
Hummers can tell the difference between dayold and two-day-old nectar flowers, and they remember fields and backyards with abundant flowers. They’ll also recall yards with hummingbird feeders.
Although it looks like hummingbirds suck nectar, they don’t. Instead, hummers poke their thin beaks into flowers or feeders while their tongues extend and retract through the beak up to 15 times per second to lap up nectar, like a cat lapping up water.
Ruby-throated hummingbird measure about 3½ inches long and weigh less than a nickel, but they’re unbelievably tough. The heart, breast and flight muscles account for 30 percent of their body mass, proportionately larger than any other bird. What gives hummers uncanny smarts is a brain accounting for 4.2 percent of their body weight, and the brain is also proportionately larger than any other bird.
Meanwhile, males dazzle us with their pulsating fiery-red throats meant to attract females for breeding. Yet the radiant red color doesn’t derive from pigmented feathers but is instead an optical illusion created by the throat’s complex feather structure bending light like a prism to refract the red spectrum of light.
Females have a mere grayish throat.
The sole job of a male is to breed. He sets up a territory, attracts a female,
mates with her, perhaps offers a little help with nest building, and then goes away. He usually mates with other females but is afterward finished with breeding duties.
Females are left to finish building a thimblesize nest in the fork of twigs and camouflaged in lichens, moss or other vegetation. She alone feeds and raises the chicks.