This is Bird Note.

As a robin hops across a lawn or garden, it cocks its head to one side and then the other.

A moment later, it jabs its yellow beak to the earth and comes up with an earthworm.

How did the robin know a worm was in that exact spot?

Did it see the worm or hear it?

Or since its movements through its feet?

Experiments with captive robins first determine the birds weren't smelling worms or sensing their vibrations.

So the birds must have been seeing or hearing them, right?

To learn more, researchers buried worms in soil in a tray.

They covered the soil with a thin but opaque sheet of cardboard, followed by more soil,

making it impossible for a robin to see the worms.

Still, the robin effectively found the worms.

The scientists concluded that robins are successfully listening for their prey, even if they can't see, smell or feel it.

For Bird Note, I'm Mary McCann.

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