This beautiful little bird which measures around 15cm is usually found in wetlands and grassy areas in the North East of Argentina. We have not yet seen this species at the reserve or indeed anywhere in Ibera but it has certainly been seen there in the past. Due to habitat loss this species is in decline. It migrates to North America in the southern hemisphere winter.
All underparts are black and it looks quite different from the front. It has a cinnamon colored nape and the back is white with brown and white wings streaked with black. The tail is short, wide and spiky.
It has a cheerful, bubbly song and is usually found in small flocks.
The female is much plainer though attractively marked. She has a dull yellow breast with brown and pale yellow streaked back and wings. She has a brown line through the crown and a line running from the nape to the eye.