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How Do Pelicans Survive Their Death-Defying Dives? | Deep Look

5 vistas· 03/04/20
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Brown pelicans hit the water at breakneck speed when they catch fish. Performing such dangerous plunges requires technique, equipment, and 30 million years of practice.

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California’s brown pelicans are one of two pelican species (once considered the same) that plunge from the air to hunt. The rest, like the white pelican, bob for fish at the water’s surface.

The shape of its bill is essential to the birds' survival in these dives, reducing “hydrodynamic drag” — buckling forces, caused by the change from air to water — to almost zero. It’s something like the difference between slapping the water with your palm and chopping it, karate-style.

And while all birds have light, air-filled bones, pelican skeletons take it to an extreme. As they dive, they inflate special air sacs around their neck and belly, cushioning their impact and allowing them to float.

Even their celebrated pouches play a role. An old limerick quips, “A remarkable bird is a pelican / Its beak can hold more than its belly can…” That beak is more than just a fishing net. It’s also a parachute that pops open underwater, helping to slow the bird down.

Behind the pelican’s remarkable resilience (and beaks) lies 30 million years of evolutionary stasis, meaning they haven’t changed much over time.

--- What do pelicans eat?

Pelicans eat small fish like anchovies, sardines, and smelt.

--- How long to pelicans live?

Pelicans live 15-25 years in the wild.

--- How big are pelicans?

Brown pelicans are small for pelicans, but still big for birds, with a 6-8 foot wingspan. Their average weight is 3.5 kg.

---+ Read the entire article on KQED Science:

https://ww2.kqed.org/science/2....017/04/25/volunteer-

---+ For more information:
U.S. Fish and Wildlife brown pelican page
https://ecos.fws.gov/ecp0/prof....ile/speciesProfile?s

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