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A Boeing 737 requires a lot of jet fuel to stay up in the air: at least 750 gallons every hour. Flying, as humans have sầu learned, takes a lot of energy. For birds, maintaining their own bodies up in the sky for hours, days, và even months can also be incredibly costly, but they've sầu at least evolved for the task. Small birds lượt thích warblers are lightweight enough that they can remain airborne by quickly flapping their wings. For heavier birds, though, flapping takes too much energy. When bird species reach the kích cỡ of a small raptor, they start khổng lồ rely on other types of flight: soaring and gliding.

Through soaring, birdsgain altitude and travel quickly by taking energy from wind currents in the atmosphere. When they glide, they use the position of their wings to deflect air downward, which creates a force called "updraft" that keeps them up in the air. There are different kinds of soaring và gliding, và birds use them in a variety of ways.

“The air is this amazing environment that's on the move sầu all the time,” says Emily Shepard, a researcher who studies animal movement at Swansea University in Wales. “It's just fascinating to lớn see how it can create both opportunities và risks for different species.” Meet some of the masters of these flying techniques.

Wandering Albatrosses

“Wandering Albatrosses are the ultimate soaring birds,” says Anders Hedenström, an animal flight expert at Sweden's Lund University. When you take a look at their bodies, you understand why: With wings reaching 11 to lớn 12 feet long from tip to lớn tip, they have the largest wingspan of any living bird. Those wings can keep their thin, cigarette-lượt thích bodies aloft for days at a time.

Wandering Albatrosses spkết thúc between 1.2 lớn 14.5 percent of their flight time slowly flappingkhổng lồ stay in the air, researchers have found. The rest of the time their wings are splayed wide. Like many other birds, Wandering Albatrosses soar by catching a ride on thermals—hot air rising from the ground—khổng lồ gain altitude. But what makes them chất lượng is their impressive sầu ability khổng lồ engage in a type of flight called “dynamic soaring,” which can only happen while flying over the ocean, says Todd Katzner, a wildlife biologist at the U.S. Geological Survey.

In dynamic soaring, albatrosses take advantage of the different speeds và directions wind flows depending on how cthua kém it is to lớn the Earth’s surface. The birds start cthua trận khổng lồ the ocean, where they catch a ride upward on athermal.They slowly climb, và when they reach high altitudes, where wind moves faster, they shift to fly in the same direction of the wind. That way, they can glide at a relatively fast speed while descending. By the time they are at lower altitudes, where wind is moving slowly, they have sầu picked up a lot of momentum and are movingfast. That lets them turn their bodies diagonally in the direction they want lớn travel, even if it's against the wind. Finally, when they are running out of energy and slowing down, they restart the cycle by catching another thermal.

Accompanied by maneuvers that use the movement of the wind rising over waves, dynamic soaring is how Wandering Albatrosses manage to lớn travel up khổng lồ 3,000 miles a week using barely any energy.

Andean Condors


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Photo: Dorian Anderson

If Wandering Albatrosses are the soaring masters of the sea, there is no doubt Andean Condors take the crown for inlvà birds. Retìm kiếm published recently showed that the Andean Condor—the heaviest soaring bird, at 35 pounds—flaps less during flight than any other free-ranging bird. After following eight Andean Condors for five sầu years, a team of European and Latin American scientists found that even young birds soar about 99 percent of their flight time. “They are the extreme version of a soaring bird. It was fascinating khổng lồ us,” says Emily Shepard, the lead author of the study.

The researchers found that these giant birds flap only during take-off & landing. They are so massive sầu that they thua altitude even when flapping as fast as they can. This means that their reliance on wind currents is nearly absolute, says Shepard. So, khổng lồ stay in the air, Andean Condors mostly use thermals lớn elevate. Once they’re high enough, they can glide between thermals looking for food. Less frequently they use another type of air current called “orographic updraft” that forms when the wind collides with an object—like a mountain or a building—and changes its direction lớn go upwards.

The researchers are now focusing on understanding the social aspects of soaring, or how a group of birds using the same air resources influence each other’s decisions—such as when to lớn jump from one thermal khổng lồ another, or picking the best spot to l& or take off, says co-author Hannah Williams.

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Great Frigatebirds


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Like many other soaring birds, Great Frigatebirds use thermals to lớn gain altitude. But unlike the others, they ride powerful thermals inside white and puffy cumulus clouds, which can elevate them 13 feet per second. “It’s the only bird that is known to enter inlớn a cloud intentionally,” Henri Weimerskirch, lead author of the paper describing this behavior, told NPR in năm 2016. By doing so thebirds can reach altitudes as high as 13,000 feet.

The amount of time they can soar without stopping is also impressive sầu. While migrating through the Indian Ocean, the birds can stay in the air for up to lớn two months, gliding between thermals while scanning for food on the surface of the sea. One tagged frigatebird traveled 34,000 miles in 185 days, stopping brieflyon small islands for just four days!Such an achievement could only be accomplished by the bird with the greademo wing-area-to-body-mass ratio in the world. It also helps that they can sleep on the wing.

American White Pelicans


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Photo: Claudio Contreras Koob

American White Pelicans have sầu a trichồng under their wing that sets them apart from other birds on this list: miniature tornados. White Pelicans migrate in flocks, arranging themselves in a characteristic V formation to lớn save sầu energy together. The separated feathers at thetip of eachbird's wing creates a force called a "wingtip vortex," Hedenström says. By flying in a V formation, each bird (except for the leader) can get lift fromthe wingtip vortex created by the bird ahead of it in line. A study on their cthua kém relative sầu, the Great White Pelican on the other side of the Atlantic, showed birds could reduce their energy expenditure by14 percentflying in this formation.

But that's not the only way American White Pelicans save energy while migrating. They also change their flight pattern depending on the season,a 2017 study revealed. While they rely on updrafts and thermalsduring their spring migration from their wintering sites in Alabama, Louisiamãng cầu, and Mississippi khổng lồ their breeding sites in the Northern Great Plains, they tend to be carried by a tailwind during the autumn, when air currents are weaker. The different strategies made their migration tốc độ significantly different: about 24 miles per hour during the spring, và trăng tròn miles per hour in the fall.

Golden Eagles


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For many birds on this list, soaring is a largely passive activity. They travel in a general direction, guided largely by wind currents, và keep their eyes open for food to scavenge or prey that's relatively easy khổng lồ catch.Golden Eagles, though, engage in more complex activities while soaring.They hunt small và medium-sizemammals. They stake out and defkết thúc territories of around 6,000 acres. They even play fetch with themselves. That complexity in behavior sets them apart from other large soaring species lượt thích vultures và condors, says Todd Katzner. “Golden Eagles, & other big eagles, are kind of quality because not only vày they soar, but they soar to do all this crazy stuff,” he says. They don’t bởi very much flapping at all: It only takes up between 3 and15 percent of their flight time.

Katzner studies a small Golden Eagle populationthat migrates và wintersalong the Appalachian Mountains. These birds don’t have access to strong thermals lượt thích their European peers residing near the Mediterranean, Katzner says. These birds have sầu had to lớn diversify the types of air currents they use to stay in the air. When migrating, they soar in thermals for about 41 percent of their flight time, glide between thermals about 45 percent of the time, & soar using orographic updraft, just lượt thích Andean Condors, about 13 percent of the time.

Turkey Vultures


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Turkey Vultures are different from other vultures throughout the world. Most vulture species rely heavily on soaring và gliding through the air at very high altitudes (up to 37,000 feet), says Katzner, và they rely heavily on sharp vision to see the carcasses of dead animals from such a height. But Turkey Vultures have adapted lớn fly at lower altitudes lớn sniff the best pieces of carrion. In fact, they have one of the best smelling systems of all birds. In 2017, after comparing them with other 32 species, a team of researchers proved that Turkey Vultures has more mitral cells, which transmit information about odors lớn the brain, than any of the other measured species.

These birds fly using a type of soaring called “contorted soaring.” Through this technique, Turkey Vultures ride the upward wind generated when air currents collide with treetops. This allows them khổng lồ stay closer to the ground compared to lớn other carrion eaters, lượt thích Blachồng Vultures in North America, giving them an advantage. They can also rock side-to-side while flying khổng lồ counteract the wind forces in turbulent scenargame ios, which allows them to lớn have sầu a lot of control và stability in their flight. “They can fly with almost no wind and in very turbulent settings," Katzner says. "They are just one of the coolest species in North American to me."

White Storks


Photo: Holger Ehlers/Alamy

White Storks spover more time flapping than the other birds on this list: It takes up about 17 percent of their flight time, which is still significantly less than most bird species.What makes them fascinating, says Hannah Williams, is how their social interactions shape the amount of soaring, gliding, & flapping of each bird.

After following a group of 27 White Storks for four years, researchers found that, when migrating, the lead bird hasa more irregular flight pattern than the rest of the flock following behind. It didn't necessarily fly in a straight line, & spent most of its timeexploring thermals. The researchers think that’s because the birdin front is in charge of finding new thermals that the other birds use to lớn gain altitude. Meanwhile, the followers in the flochồng flapped more often to lớn avoid falling behind the group.

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In the kết thúc, these differences influenced where follower & leader storks spent the winter. Frequent-flapping follower birds spent more energy and were able to lớn fly only 621 miles (1,000 kilometers)from Lake Constance—where Germany, Switzerl&, & Austria meet—lớn Spain. The leaders, on the other hvà, were able lớn fly more than 2,485 miles (4,000 kilometers), wintering in northern Africa instead.


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