How Do Finches Shell Sunflower Seeds so Quickly?

It's all thanks to a specialized beak.

This audio story is brought to you by BirdNote, a partner of the National Audubon Society. BirdNote episodes air daily on public radio stations nationwide.

Transcript: ​

This is BirdNote.

Birds like finches and cardinals love sunflower seeds, which they take into their stout, triangular beaks one after the other. In the blink of an eye, they extract the nutritious contents, and they do it so fast, it looks like a magician’s sleight of hand. But if we magnify the process and slow it down, we can see how it works. 

First, if we look inside a finch’s beak, we see a groove that runs the length of the beak on the cutting edge of the upper half. The lower half of the beak slides into it perfectly.  

When a finch plucks a sunflower seed from the feeder, its uses its tongue to maneuver the seed lengthwise into that groove. As it closes its beak, a slight back and forth action slices open the hull, and a small sideways movement husks the seed, while the tongue may help extract the kernel. Now it’s quickly on to the next seed: maneuver, slice, husk and extract, swallow.

Chickadees lack the heavy duty, seed-slicing beak of a finch. But they still partake of countless sunflower seeds. A chickadee takes one sunflower seed at a time from the feeder, flies to a nearby perch where it can hold the seed atop a branch, then hammers and chips the hull open with the tip of the bill to extract the goods.

For BirdNote, I'm Michael Stein.

Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Northern Cardinal recorded by G. A. Keller.
BirdNote's theme music was composed and played by Nancy Rumbel and John Kessler.
Narrator: Michael Stein
Producer: John Kessler
Executive Producer: Dominic Black
© 2016 Tune In to Nature.org    February 2015/2018  


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