This American Goldfinch is unmistakable in his bright yellow breathing plumage.

Come late this summer in the northern United States, though,

and his feathers begin to look a little ragged.

This bird is getting ready to migrate south for the winter.

And after its last migration, a busy breeding season,

and exposure to the elements, it's time for a new set of feathers.

While the Goldfinch is growing new flight feathers in a process called molting, he's not as nimble on the wing. That makes it awkward to gather food, and he's more vulnerable to predators. Yikes!

Just to be safe, this Goldfinch makes a pit stop at a secondary location, away from the breeding ground to undergo the indignities of molting.

Lots of songbirds make these migratory detours to change out their feathers, usually between their big spring and fall journeys.

It's called molt migration.

Birds in the west are more likely to travel farther from their breeding grounds to find safe havens, but scientists are noticing this behavior in bird species across the U.S.

To protect birds during this exposed stage,

molt-migration habitats could be important targets for future conservation efforts.

For bird-m efforts. For Bird Note, I'm Mark Bramhill. You're going to be.