| Geese and other large birds such as cranes and pelicans often fly in energy-saving formations. The updraft produced by the wing tips of birds flying in formation helps to lift the neighboring birds and saves them energy over long distances. These formations range from the familiar "V" of these geese to the staggered line in which pelicans often fly. |
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Gliding and soaring on long thin wings, albatrosses can travel many miles over the ocean without flapping. From high above the waves, they glide with the strong ocean winds. As the birds lose altitude, the wind becomes weaker because of friction with the ocean surface. Just above the waves, albatrosses turn into this weakening wind and, using their momentum, effortlessly soar back up to where the wind is stronger. Then they turn and coast back down again. |
| Gulls, hawks, and many other birds take advantage of an energy-saving "elevator." It is created when wind veers upward as it runs into an obstruction such as a cliff or mountain. Birds can float effortlessly on these uprising winds. |
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Birds with large, broad wings such as eagles and vultures can soar upward on rising columns of warm air called thermals. Warm air is lighter than cold air and rises from the ground to be replaced by heavier cool air. Thermals are often found over fields, tall buildings, and parking lots. Most birds that use thermals are searching for prey or carrion, but some birds, like storks, use thermals to migrate, climbing within them, then coasting downward to the next thermal. |
