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How Pelicans learn to fish




Of course the first thing I thought of was pterosaurs...

http://www.nytimes.com/2010/10/26/science/26qna.html

Q. How do pelicans learn to dive for fish?

A. Young pelicans learn to feed themselves through a combination of trial and error, imitation of adult birds and instinct, bird experts suggest.

In the United States, the Eastern brown pelican (Pelecanus occidentalis carolinensis) and the California brown pelican (Pelecanus occidentalis californicus) make dives onto schooling fish from impressive heights or float on the surface to scavenge fish. A dive from 30 to 60 feet up, or even higher, hits the water with considerable force. Fish a few feet below the surface are scooped up, and water drains from the sides of the pouch. They tilt their heads back and swallow on the spot.

For young pelicans, some early experience in diving for fish comes during their time in the nest, when they graduate from feeding on half-digested fish bits regurgitated by their generous parents to retrieving fish from the famously capacious pouched parental bills and even their gullets. The nestlings may dive in shoulder deep to make the parents disgorge fish. Pelicans are well fed in the nest for 9 to 11 weeks, by which time they are fully feathered and ready to go out on their own.

Their diving success rate is highly variable and depends on experience. Adult California brown pelicans bring up fish from around two-thirds of their dives, while novices appear to have a lot of trouble; fewer than half survive their first year out of the nest.



Didn't know the mortality rate was that high.

Much has been written and speculated regarding pterosaur flying, but
what about smacking the water?