A little bird told me...

The red-necked grebe has a bit of a split personality - in fact, it only lives up to its name for about half the year. Its feathers are not red but brambly brown and grey throughout the winter, when it lives a quiet life in ocean waters along the European and North American coasts. But, just before it migrates to a northerly lake, pond or swamp for breeding season, the plumage around the grebe's throat turns a distinctive rust-red. Both males and females undergo the plumage change.
© Edo van Uchelen/Minden Pictures