Adult birds are unmistakeble, with a chestnut head and neck.
Both sexes are similar in lumage.
The juvenile bird is rusty-brown overall, with black barring and white spots.
Its throat, central chest and belly are white.
It takes some five years to acquire adult plumage.

1st, 2nd & 3rd photo: A juvenile. Sandoval Lake, Puerto Maldonado, Peru, 20 June 2009
4th photo: An adult. Reserva Ecologica Taricaya, Puerto Maldonado, Peru, 28 May 2009

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