Pantanal

Lore & Background

The name 'Pantanal' comes from the Portuguese word pântano and the Spanish word pantano, meaning 'swamp' or 'wetland,' plus the suffix -al, indicating abundance. The region is a gently sloped basin formed by a large, concave, pre-Andean depression of the Earth's crust related to the Andean orogeny of the Tertiary. It constitutes an enormous internal river delta where several rivers from the surrounding plateau merge, depositing sediments that have filled the depression. The Pantanal is bounded by the Chiquitano dry forests, Arid Chaco, Humid Chaco, and Cerrado savannas.

Reader's Guide

The Pantanal is significant as the world's largest tropical wetland and flooded grasslands, hosting a vast array of biodiversity. Its ecosystem includes approximately 463 bird species, 269 fish species, over 236 mammal species, 141 reptile and amphibian species, and over 9,000 invertebrate species. The apple snail is a keystone species, recycling nutrients in anoxic waters during seasonal floods. The region is home to endangered species such as the marsh deer, giant river otter, hyacinth macaw, and one of the largest jaguar populations on Earth. Threats include commercial fishing, cattle-ranching on 99% of privately owned land, and erosion from agricultural activities. Despite low deforestation rates (less than 17%), these pressures alter the hydrological and soil characteristics of the floodplains.

Did You Know?

• The Pantanal covers an area estimated between 140,000 and 195,000 km².
• Roughly 80% of the Pantanal floodplains are submerged during the rainy seasons.
• The apple snail (Pomacea lineata) is an invasive species in the Pantanal, not a native keystone species.
• The Pantanal is home to a large population of yacare caimans, though estimates of 10 million individuals are disputed.