Brownish elaenia the Xingu River in the south of Pará state, North Region, Brazil; it ranges upstream on the Xingu for 700 km, then a tributary to the west of the Xingu, the Rio Iriri, for another 700 km. The next upstream tributary for the bird's range, is the Madeira River in the Amazon Basin's southwest, Amazonas state. The range proceeds 2400 km upstream into the headwaters of the Madeira in northern Bolivia. To the west the brownish elaenia's range continues as the Amazon River becomes the Marañón River and proceeds to the headwaters in northern Peru; this is also along the
Xingu River in the Xingu River Basin and it is estimated that the total is around 600 fish species, including many endemics. At least 193 fish species living in rapids are known from the lower Xingu, and at least 26 of these are endemic. From 2008 to 2018 alone, 24 new fish species have been described from the river. Many species are seriously threatened by the dam, which will significantly alter the flow in the Volta Grande rapids. In the Upper Xingu region was a highly self-organized pre-Columbian anthropogenic landscape, including deposits of fertile agricultural terra preta, black soil in Portuguese, with