FAUNA PARAGUAY ECO-REGIONS

Paraguay lies at the meeting point of six eco-regions, diminishing and unique habitat types with high levels of reginal endemism. The eco-regions found in Paraguay are - Dry Chaco, Humid Chaco, Cerrado, Pantanal, Argentinian Mesopotamian Grassland and Atlantic Forest. Below we give a brief rundown of the major characteristics of the five eco-regions.

Argentinian Mesopotamian Grasslands
Also known as Paraná flooded grassland, the bulk of this unique habitat occurs in northern Argentina´s low-lying Mesopotamia regions, encompassing the provinces of Misiones, Corrientes and Entre Rios, and reaching only extreme southern Paraguay in the departments of Ñeembucú, Misiones and Itapúa. AMG is conspicuously marshy with permanent and periodically inundated areas interspersed with a mosaic of other habitats, especially gallery forest and freshwater bodies. Whilst large areas of this diminishing habitat are protected in Argentina, not least by the Reserva Natural del Iberá, that of Paraguay is under serious threat from agriculture and cattle ranching. Drainage and burning of tall stands of natural grass is also a serious problem.

Atlantic Forest
Actually a complex of 15 eco-regions, the Paraguayan humid forest is classed as Alto Paraná Atlantic Forest (BAAPA). Historically the Atlantic forest covered an extensive stretch of coastal eastern Brazil, north-eastern Argentina and eastern Paraguay, however much of this forest has been cleared and only 8% of Paraguay´s original forest still remains. The natural vegetation of this eco-region is a mosaic of humid forest and scrubby clearings (capuera) interspersed with savanna formations. Rainfall is high and, in Paraguay at least, there is no defined dry and wet season - rain falls throughout the year. Botanical diversity is extremely high in this eco-region, with endemism estimated at upwards of 53%. Logging and clearing of forest for agriculture remain the biggest threats to the Paraguayan Atlantic forest, much of which has already been lost forever. The inception of the Itaipú Dam complex destroyed vast areas of virgin forest in the Alto Paraná region, completely flooding a set of waterfalls comparable to those at Iguassu, and proposals for more dams threaten to do the same. A lack of local knowledge of the importance of the forest, widely dismissed as “monte”, results in wanton and reckless destruction for very little gain.

Cerrado
The largest savanna region in South America and biologically the richest and most diverse on earth, the cerrado reaches its southern limits in Paraguay. A vast area, it stretches from Central Brazil to eastern Bolivia and south to the north-eastern Orient of Paraguay. Typical cerrado is savanna-like vegetation that grows on nutrient poor and well-drained soils, but there is considerable diversity within this eco-region, from open field campo limpio to closed cerrado woodland or cerradón. UNESCO classifies the Paraguayan cerrado as “medium-tall grassland with broad-leaved evergreen tree synusia”. It has been estimated that only 33% of South America´s cerrado remains unmodified by human activity, and only 1% currently receives protection. The expansion of agriculture is the biggest single threat to this important eco-region.

Dry and Humid Chaco
The Chaco meaning “place of excellent hunting” in the Quechua language, does indeed boast extraordinary numbers of game animals. The bulk of this region is in western Paraguay and northwestern Argentina, with a slight extension into extreme southern Bolivia. The Paraguayan Chaco actually composes two eco-regions, the Dry Chaco (approximating to the Alto Chaco) and the Humid Chaco (approximating to the Bajo Chaco), the latter wetter and dominated by palm savanna and seasonally-flooded grassland. Generally speaking rainfall is low and temperatures are high. Typical habitats of the Chaco are semi-arid, with matorral and thorny forest dominant. Thorny bushes and cacti occur alongside scattered xerophytic trees, with thorny terrestrial bromeliads and star catus providing the undergrowth. Species diversity is high and specialised, and the Chaco is an important stopover for migrating waterbirds. Though much of the Paraguayan Chaco remains uninhabited and largely unspoilt, pressure from cattle grazing remains a problem. The construction of the Trans-Chaco highway has opened up previously remote areas to hunters, settlers and developers and Chaco woodland is under threat from loggers keen to exploit the hard imperishable wood. Resultant habitat clearance could lead to desertification

Pantanal
The world´s largest wetland area, the Pantanal eco-region exhibits breathtaking floral and faunal diversity. Defined by UNESCO as “tropical tall grassland” it is geologically young, dating from the last glacial, and so endemism is low. Located approximately centrally in the South American continent, the bulk of it is in Brazil, and only its outskirts reach eastern Bolivia and Paraguay. The majority of the region is formed by the floodplain of the Rio Paraguay and, being essentially a flat area, it floods regularly, with up to 78% of the land submerged during the wettest periods. Floating plants are the most important primary producers, reaching a higher diversity here than anywhere else on earth, while the seasonally-flooded areas are dominated by herbaceous plants adapted to extremes of flood and fire. Gallery forest is typical closer to the permanent water sources that flood less often. Currently the principal threat to this eco-region comes from pesticide run-off from agricultural land and pollution from gold-mining endeavours. Legal and illegal poaching is a problem, but the a much more serious threat is posed by the “Hidrovia” project, jointly proposed by the governments of Brazil, Paraguay and Bolivia. Designed to open the Rios Paraguay and Paraná up as major shipping lanes, and involving the construction of various ecologically catastrophic damming schemes, Hidrovia has the potential to completely drain the Pantanal floodplain.