The mighty Paraguay River starts just north of Brazil's Pantanal, and gains force as it slowly works south. When it hits the Paraguayan border it is already a major river, and gains in volume as it travels south traversing Paraguay to Asuncion. From there, it forms the border of Argentina and Paraguay down to its confluence with the Paraná River near Resistencia.
The Pantanal ecosystem follows the river's edge and in the Argentine portion becomes more accessible than in any other region outside Brazil. The 8,000 square miles of Ibera wetlands are found south of the Paraná River, this forms the southern border of Paraguay with Argentina. In both wetland systems, seasonally flooded grasslands, marshes, palm savannas and lakes host a number of mammals, reptiles and birds. We can see the Yacare Caiman, Marsh and Pampas Deer, Black-and-Gold Howler Monkeys and Bare-ear Marmosets, and occasionally the rare Maned Wolf and Giant Anteater.
Bird species include the rare and gaudy Black-hooded Parakeet, Blue-fronted Parrot, Large-billed and Yellow-billed Terns, Chotoy Spinetail, rare, elusive and local flycatchers including the Streamer-tailed, Strange-tailed, Cock-tailed and Sharp-tailed Tyrants, Bearded Tachuri, Black-and-white Monjita, Blue-billed Black-tyrant and others. All three South American storks, the Jabiru, Wood and Maguari, can be seen.
This is also the best place to see several uncommon and very local seedeaters, including the Dark-throated, Marsh, Chestnut and more common Rusty-collared, Tawny and Capped Seedeaters. Icterid possibilities include Screaming Cowbird, Chestnut-capped, Unicolored, Scarlet-headed and Chopi Blackbirds along with the rare Saffron-cowled Blackbird.