Land Between Rivers
In a relatively undeveloped corner of Argentina sits an ecoregion that’s surrounded by flowing rivers. Called the Southern Cone Mesopotamian Savanna, it’s a mixture of savannas, wetlands, and subtropical forests and is home to a diversity of rare birds and unusual mammals. But a growing human population could threaten this diverse system as people move from the bustling capital of Buenos Aires to this fertile grassland habitat.
Located between the Parana River to the west and the Uruguay River system to the east, this ecoregion is known locally as "Entre Rios," or "between rivers." Being surrounded by rivers has its advantages, as this is one of the least developed areas around Buenos Aires, even though the city--one of the largest in Latin America--is quite close. The area is a mosaic of savannas and vast wetlands with patches of subtropical forest and palm savannas.
This ecoregion supports a number of rare and threatened birds. An endemic subspecies of the marsh seedeater, Narosky’s seedeater, is one example. Other birds include the spotted nothura, glaucous-blue grosbeak, brown cachalote, red-winged tinamou, bare-faced ibis, striped owl, and scissor-tailed nightjar. Mammals in this area include the maned wolf, black howler monkey, zorro do monte (fox), pampas fox, coati, crab-eating raccoon, tayra, grison, giant river otter, ocelot, margay, marsh deer, jaguar, South American water rat, and cavy--a type of guinea pig. In the remaining palm savannas along the Uruguay River there are also rheas, capybaras, vizcachas, and pit vipers. Here you might see flocks of ibis roosting in an open grassy marsh with caiman lying along the muddy banks and a bittern wading through a patch of blooming purple water hyacinth. In the dryer areas, among a stand of tall palms, rheas and marsh deer feed in the distance as a group of coatis bully a crab-eating raccoon out of its lunch.
Cause for Concern
In the early 1900s, much of the area was cleared and drained for a promising cattle industry, which never quite got started. Today, because of increasing population growth in the area today, there is strong pressure to convert lands to agriculture and housing.
For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.All text by World Wildlife Fund © 2001