Drake Rosybill Pochard from South America with red eye, massive black-tipped red bill and, in sunlight, purple head.
Although both from South America, the Rosybill Pochard and Chiloe Wigeon make an unlikely couple.
The bill has a face-shield.
The female Rosybill Pochard has a lesser version of the raised face-shield on her beak (sometimes with white on her face, sometimes not).
Both genders have white rumps.
Her chin is white.
His grey flanks and black upper back are "vermiculated" (made up of very fine grey/white or black/grey wavy lines).