This is Bird Note.

At the edge of the Arctic lies the vast boreal forest.

In summer, it's home to legions of nesting birds, from warblers to loons.

In early autumn, nearly all these birds depart for warmer points south.

By November, this dark land of spruce and furs is a cold, forbidding place.

Yet one remarkable songbird stays behind, the Boreal chickadee.

This tiny dark-capped fluffball lives here year-round. How do boreal chickadees survive the harsh winter?

First, during summer, they cash a great deal of food, both insects and seeds. Moths and beetles and even

aphids are stashed away in bark crevices and under rough edges of lichens.

The chickadees also store a lot of spruce seeds.

Then in fall, the birds put on fresh, heavier plumage,

and their feathers are more dense than most birds,

creating a comfy down parka for the chickadee.

And most impressive, the chickadees adapt to deep cold by lowering their body temperature at night from 108 degrees to just 85 degrees.

In this way, the birds conserve their stores of insulating fat.

So hats off to the boreal chickadee, a truly rugged bird,

even if it weighs only one-third of an ounce.

For Bird Note, I'm Mary McCann.