is heavy. It droops and dangles over its sturdy stem. Just inside its red and yellow petals lies a sugar-rich liquid called nectar. T is fl ower sits undisturbed in a fi eld of fl owers in southeastern Alaska. But it doesn’t sit undisturbed for long. A humming sound drones in the distance.
T
T e sound gets closer and closer. Suddenly, a fl utter of bright orange feathers fl ashes in front of the bloom. It’s a tiny bird called a rufous hummingbird. T e rufous is one of the world’s smallest yet strongest warm-blooded animals. T is male buries his bill in the tube-shaped
fl ower and laps up the nectar with its tongue. In seconds, the fl ower is drained, and the bird moves on to the next fl ower. And the next. And the next. Before long, he will have eaten from almost every fl ower in this fi eld. T at’s not unusual. Hummingbirds are always eating. But this one has a special need to fuel up. He’s about to take off on a very, very long fl ight.
he bloom of the western columbine fl ower
Fueling Up Summer in Alaska is mild, and food is plentiful. T e rufous is the only hummingbird that fl ies this far north. It’s late summer now, though. T e bird senses that winter’s chill is on the way. It’s time to head south where nectar-bearing fl owers will be blooming all winter. What comes next will be a marathon fl ight
all the way to Mexico. T e journey south is more than 5,600 kilometers. It’s one of the longest migrations of any bird on Earth. To fl y this far, this bird will need a lot
of fuel. To get the energy he needs, he will visit hundreds of fl owers every day. A hummingbird’s metabolism is very high. T at means its body uses up energy quickly. Typically, a hummingbird eats about half of its body weight in a single day. T at would be like a 32-kilogram person eating 16 kilograms of food every day! A hummer’s favorite food is nectar. But it
doesn’t use its beak like a straw to suck in or up the nectar. As the hummingbird hovers near a blossom, it steadies its needle-like bill. Its long, elastic tongue stretches out to probe the fl ower. A hummer’s tongue is as thin as a thread and is forked at the end. Each half of the fork rolls inward to make a hollow trough. As the trough fi lls with nectar, the hummer pulls in its tongue to drink. It’s a fast and effi cient way for the hummingbird’s body to take in a lot of nectar. Hummers quickly convert the sugar in the
nectar to energy. It takes about 15 minutes. During that time, they rest and save energy by perching on twigs. T en they’re ready to zoom off again and grab the next snack. Getting ready to migrate takes a lot of
The western columbine is a favorite source of nectar for the rufous hummingbird.
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snacking. T e rufous hummingbird needs to store fat equal to about half his body weight. In addition to nectar, he might drink sweet sap from holes in trees made by another bird, the sapsucker. Or he could eat insects, which supply nutritious protein. He could snatch ants or beetles off of leaves. He might steal fl ies or wasps from spider webs. T e rufous might even dive-bomb insects in mid-air.
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