Vast grasslands and extensive wetlands attract aquatic birds that feed themselves gently during the day. With the sunset, they take off and, in a large swarm, let themselves be heard in thousands of voices until nightfall. Such is the spectacle offered each day by the great wetlands of Ñeembucú, a region that conforms the most extensive system of wetlands on the planet, originating in the Great Wetlands of Brazil and connecting with diverse sub-systems across the Paraguay River, including the Lower Chaco, Arroyos y Esteros and the gigantic Ypoa Lake. This region is even more interesting due to the fact that one can find areas in which the vegetation and fauna are those associated with the Lower Chaco. This makes it able for the traveller to experience all the diversity associated to the great wetlands, as well as the typical connotations of the Chaco and profile.

Enjoy canoe trips through wetlands and pastures that look like oceans, hiding birds of vivid colors, like the Scarlet-headed Blackbird (Amblyramphus holosericeus) and the Rusty-collared Seedeater (Sporophila collaris), or families of otters that, once in a while, show their moustaches above the surface. The great Mesopotamian Grasslands of which also are part wetlands of Ñeembucú is an encounter with southeast Paraguayan nature; an encounter one can not postpone.

This region is characterized by extensive pastures and wetlands. In the southeast of the region with drier grasslands, it represents a northern extension of the South American Mesopotamian Savannas, present to the Northwest of Uruguay, extreme south of Brazil and North Central of Argentina. To the west with more humid pastures is an extension of the Humid Chaco in the Eastern Region of Paraguay.

This ecoregion has registered in Paraguay a total of 403 species of birds of which 4 are considered endemic to this Ecoregion at the global level. Below is the list of Mesopotamian Grassland endemic birds that are found in Paraguay: Bay-capped Wren-Spinetail, Ibera Seedeater, Marsh Seedeater and Chestnut Seedeater.