The Pantanal (, ) is a natural region encompassing the world's largest tropical wetland area, and the world's largest flooded grasslands. It is located mostly within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay. It sprawls over an area estimated at between . Various subregional ecosystems exist, each with distinct hydrological, geological, and ecological characteristics; up to 12 of them have been defined.

Roughly 80% of the Pantanal floodplains are submerged during the rainy seasons, nurturing a biologically diverse collection of aquatic plants and helping to support a dense array of animal species.

Etymology

The name "Pantanal" comes from the Portuguese word and the Spanish word that mean "swamp", "wetland", "bog", "quagmire", or "marsh" plus the suffix -al, that means "abundance, agglomeration, collection".

Geography and geology

The Pantanal covers about of gently sloped basin that receives runoff from the upland areas (the Planalto highlands) and slowly releases the water through the Paraguay River and tributaries. The formation is a result of the 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, in which several rivers flowing from the surrounding plateau merge, depositing their sediments and erosion residues, which have been filling the large depression area of the Pantanal. This area is also one of the distinct physiographic provinces of the larger Parana-Paraguay Plain area, which encompasses a total of .

The Pantanal is bounded by the Chiquitano dry forests to the west and northwest, by the Arid Chaco dry forests to the southwest, and the Humid Chaco to the south. The Cerrado savannas lie to the north, east, and southeast.

Climate

The Pantanal is a tropical wet and dry region with an average annual temperature of and rainfall between per year. Extreme temperatures can reach a high of or drop to .

Fauna

The Pantanal ecosystem is home to some 463 species of birds, 141 species of reptiles and amphibians, and over 9,000 subspecies of invertebrates.

The apple snail (Pomacea lineata) is a keystone species in Pantanal's ecosystem. When the wetlands are flooded once a year, the grass and other plants will eventually die and start to decay. During this process, decomposing microbes deplete the shallow water of all oxygen, suffocating larger decomposers. Unlike other decomposing animals, the apple snails have both gills and lungs, making it possible for them to thrive in anoxic waters where they recycle the nutrients. To get oxygen, they extend a long snorkel to the water surface, pumping air into their lungs. This ability allows them to consume all the dead plant matter and turn it into nutritious fertilizer available for the plants in the area. The snails themselves are also food for a variety of animals.

Among the rarest animals to inhabit the wetland of the Pantanal are the marsh deer (Blastocerus dichotomus) and the giant river otter (Pteronura brasiliensis). Parts of the Pantanal are also home to the following endangered or threatened species: the hyacinth macaw (Anodorhyncus hyacinthinus) (a bird endangered due to smuggling), the crowned solitary eagle (Buteogallus coronatus), the maned wolf (Chrysocyon brachyurus), the bush dog (Speothos venaticus), the South American tapir (Tapirus terrestris), and the giant anteater (Myrmecophaga tridactyla). Common species in the Pantanal include the capybara (Hydrochoerus hydrochaeris), ocelot (Leopardus pardalis), and the yacare caiman (Caiman yacare). According to 1996 data, there were 10 million caimans in the Pantanal, making it the highest concentration of crocodilians in the world. The Pantanal is home to one of the largest and healthiest jaguar (Panthera onca) populations on Earth.

There are thirteen species of herons and egrets, six species of ibises and spoonbills, and five species of kingfishers that use the Pantanal as a breeding and feeding ground. There are nineteen species of parrots documented in the Pantanal, including five species of macaws. Some migratory birds include the American golden plover, peregrine falcon, and the bobolink.

Most fish are detritivores, primarily ingesting fine particles from sediments and plant surfaces. Most species are not under threat due to the low deforestation rates (less than 17%) of native vegetation now in the area due to new regulations.

Some of the causes which threaten the Pantanal ecosystems are:

  • Fishing
  • Commercial fishing is focused on only a few species and is probably not sustainable. National and international sport fishing in the Paraguay river and its tributaries are the main focus for fishing activities.
  • Erosion and sedimentation caused by this activity alter the soil and hydrological characteristics of Pantanal flood-plain ecosystems; consequently, native species are threatened by the change in ecosystem variables. Reptile, wildcat, and parrot species are particularly at risk from the smuggling industry due to their high value on the black market.
  • Uncontrolled tourism and overuse of natural resources
  • In some areas of the Pantanal, particularly popular jaguar-viewing sites, increasing wildlife tourism has raised concerns about disturbance to animals, with reports that frequent boat traffic may alter jaguar behaviour and increase habituation to humans.
  • Deforestation
  • Establishment of logging companies during political turmoils in the region resulted in peak deforestation rates between 1978 and 1989. Many livelihoods were dependent on harvesting rubber trees as new waves of migrants arrived, resulting in what is now there today.
  • Forest fires
  • In late 2020, a quarter of the wetland was destroyed by an unprecedented fire attributed to climate change. An area estimated of about was razed by the fire, killing millions of vertebrates. Experts say 2020 was the most active year on record for wildfires. Until November 2020, Brazil's National Institute for Space Research (INPE) had detected more than 21,200 fires in the Pantanal biome, a figure that is 69% higher than 2005, when the INPE recorded roughly 12,500 fires. There were 8,106 fires in September 2020 alone—more than four times the historic average for the month.
  • Climate change
  • Current predictive climate models indicate a progressive increase in the frequency of extreme events (for example, extreme rainfalls and extended droughts). These events could affect the Pantanal's ecosystem functioning, amplifying and worsening human modifications of hydrological and environmental conditions in the basin.

Protected areas

thumb|Hotel SESC Porto Cercado in the SESC Reserve

A portion of the Pantanal in Brazil has been protected as the Pantanal Matogrossense National Park. This park, established in September 1981, is located in the municipality of Poconé in the State of Mato Grosso, between the mouths of the Baía de São Marcos and the Gurupi Rivers. The park was designated a Ramsar Site of International Importance under the Ramsar Convention on May 24, 1993.

Encontro das Águas State Park and Guirá State Park are state parks of Mato Grosso in the Pantanal.

The SESC Pantanal Private Natural Heritage Reserve (Reserva Particular do Patrimonio Natural SESC Pantanal) is a privately owned reserve in Brazil, established in 1998 and in size. It is located in the north-eastern portion, known as "Poconé" Pantanal, not far from the Pantanal National Park. It is a mix of permanent rivers, seasonal streams, permanent and seasonal floodplain freshwater lakes, shrub-dominated wetlands and seasonally flooded forests, all dedicated to nature preservation, and was designated a Ramsar Site of International Importance under the Ramsar Convention.

Otuquis National Park and Integrated Management Natural Area and San Matías Integrated Management Natural Area are protected areas of Bolivia in the Pantanal. The entrance to Otuquis National Park is through the town of Puerto Suarez.

Main cities

Brazil:

  • Miranda, Mato Grosso do Sul
  • Aquidauana, Mato Grosso do Sul
  • Barão de Melgaço, Mato Grosso
  • Bodoquena, Mato Grosso do Sul
  • Bonito, Mato Grosso do Sul
  • Cáceres, Mato Grosso
  • Corumbá, Mato Grosso do Sul
  • Coxim, Mato Grosso do Sul
  • Ladário, Mato Grosso do Sul
  • Poconé, Mato Grosso

Bolivia:

  • Puerto Quijarro, Santa Cruz
  • Puerto Suárez, Santa Cruz

Paraguay:

  • Bahía Negra, Alto Paraguay
  • Fuerte Olimpo, Alto Paraguay

See also

  • Wildlife of Brazil
  • Iberá Wetlands
  • Great Black Swamp, a former wetland in Ohio, US

References

  • Pantanal maps and tourist information
  • Pantanal Nature. Information on wildlife in Pantanal.
  • Patanal bird checklist