(Description from Wikipedia, the free encyclopedia)

The Giant Coot (Fulica gigantea) is a species of bird found at lakes
in the altiplano from central Peru, through western Bolivia, to north-
eastern Chile and extreme north-western Argentina. With a total
length of 48–64 cm (19–25 in),it is among the largest members of
the Rallidae family and adults are generally considered flightless. It
is the only coot with reddish legs.

As in the related Horned Coot, the Giant Coot is monogamous and
the pair builds a huge nest in a highland lake. However, unlike the
Horned Coot, the nest of the Giant Coot is primarily made of
aquatic vegetation and – as it is fiercely territorial – it never forms
colonies.
Photo from Wikipedia
Giant Coot