This is BirdNode.

That's the sound of a red cross-bill.

Cross-bills travel in a small flock in search of seeds from the cones of pine,

spruces, and furs.

How they obtain those seeds involves a curious adaptation of their build.

First, cross your fingers, like one does for good luck.

Now, just like your fingertips, the long tips of the cross-bills upper and lower bill don't meet,

but instead cross over each other.

To feed, the bird first detaches a cone from a conifer,

and holds that cone parallel to the branch with its feet.

The bird then bites between the scales of the cone,

and pries them apart by opening its carefully crafted bill.

Holding the scales apart, the bird then dislodges the seed with its tongue.

Red cross-bills search for cones on the tops of the trees,

climbing around using their feet and bills, much like parrots,

and strangely, they'll breed in winter if the cone crop is good enough.

For Bird Note, I'm Michael Stein.

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