This is Scientific American 62nd Science.

I'm Julia Rosen.

Got a minute?

Great frigate birds are extraordinary creatures.

They're seabirds with six foot wingspans, yet they only weigh about three pounds.

Their preferred food, flying fish, which they pluck out of the air above the water's surface.

Frigate birds feathers aren't waterproof, so landing on the water to fish is a no-go.

Now scientists have discovered that great frigate birds do something else amazing.

They can fly for up to two months at a time without landing.

Researchers already knew that these birds took extended trips over the Indian and Pacific

oceans to feed.

But in a new study, scientists used tracking devices to follow the movement and vital signs of birds from the island of Europa near

Madagascar. They discovered that the birds have a highly specialized strategy for staying

aloft. When they are traveling most of their time they flap very unfrequently their wings.

Henri Weimer Scurch, an ecologist at the National Center for Scientific Research in France.

In fact what they are doing, they are doing a sort of roller

cost of flight or they take altitude, even they can climb up to three or

four thousand meters and when they climb they do not flap the wing at all.

Wimer Scurch and his colleagues found that the birds climb currents of rising air associated

with cumulus clouds circling upwards the way hawks and vultures do over land.

Then they glide back down again, hardly flapping. By using atmospheric conditions to their

advantage, the birds covered an average of 420 kilometers a day almost effortlessly.

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