This is Birdnode.

It's a warm sunny day, and we're watching an American Robin sitting on the ground.

Its wings outstretched and its tail splaid out behind it.

If you look more closely, you might see something a bit shocking.

The Robin is sitting on top of an ant hill, and ants are swarming all over its body.

You might even see the Robin take an ant in its bill, and wipe it underneath its wings.

So, what's happening?

Well, it's kind of like an avian spa treatment.

Ornithologists call it anting.

Although you might not see it too often, more than 250 species of birds have been recorded

doing it.

The purpose of anting remains something of a mystery.

Although most experts agree, it has to do with transferring the ants' secretions to the

bird's body.

It's likely that the ants' formic acid helps the bird control feather mites and other parasites.

Some birds have been seen using citrus fruits, mothballs, and even glowing embers to achieve

the same effects.

One clever bird, a rook, the British cousin of the American crow, even learned to strike

a match.

Then, touch the hot tip under its wing.

Talk about a hot spa treatment.

For bird note, I'm Michael Stein.

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