It's December in Ohio. You're out doing a little bird watching in a deciduous forest.

Your boots crunch in the snow as you stroll between the trunks of leafless maple and elm trees.

So far, it's been a quiet day. The only birds you've seen in the last hour were a couple of crows and an American robin.

But suddenly you hear some Carolina chickadees calling among the branches of a large maple in front of you. You focus on one

in your binoculars. Now you hear a tufted titmouse too.

Lowering your binoculars to widen your field of view, you see that the tree is positively taming with little birds.

Besides several chickadees and a couple titmice, there's a white-breasted nut hatch

scrambling around on the tree's trunk, and there's a brown creeper close by.

Oh, and now there's a pair of tiny golden-crown kinglets, too.

You also spot a downy woodpecker on a large branch pecking at a patch of rotten wood.

What is happening?

Your heart is beating fast and you've got a big stupid grin on your face because

this is such a wonderful sight. A moment ago, the white woods were silent and still. Now you're

enjoying the antics of an entire flock of charming birds. You pat yourself on the back for being

such a keen-eyed and excellent birder.

Never mind that you didn't find the birds so much as they just showed up where you happened to be.

After only a few minutes, the little beasts flit away and disappear into the winter forest.

Congratulations! You have just witnessed what some call a bird wave or a bird party. An experience like this can be exhilarating.

Ornithologists have a more technical name for this phenomenon. It's called a mixed species foraging flock. Hello and welcome.

This is the Science of Birds.

I am your host, Ivan Philipson.

The Science of Birds podcast is a lighthearted, guided exploration of bird biology for lifelong learners.

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