Why South America’s Pantanal and Gran Chaco Region Is Crucial to Conserve

Overview

Over the next decade, conservation strategies designed to empower stewardship by local communities, Indigenous peoples, and landowners will be pivotal in conserving South America’s Pantanal and Gran Chaco region. These two biologically rich, diverse environments—the Pantanal, the world’s largest tropical wetland,¹ and the intact portions of the Gran Chaco dry forest—contain thousands of distinct plant and animal species.² Spanning Argentina, Bolivia, Brazil, and Paraguay, these areas also provide a wide variety of vital ecosystem services, such as carbon storage, migration routes, and flood control capabilities that benefit people and wildlife both in the region and downstream. 

Unfortunately, the Gran Chaco has experienced substantial deforestation because of the expansion of industrial agriculture, driven primarily by global demand for soy.³ Increased soy farming on the highlands surrounding the Pantanal has also degraded springs and rivers crucial to the Pantanal’s annual flooding pattern. Many species of flora and fauna are dependent on this wet-dry cycle, in which the lowland area’s rivers flood and recede annually and the surrounding land acts as a sponge that absorbs and then gradually releases the water throughout the year.⁴

Although the Pantanal and Gran Chaco biomes’ freshwater and dry forests cover an immense area larger than the state of California, they have received less international attention than their other counterparts in South America, such as the Amazon and Patagonia.

The Pew Charitable Trusts is working alongside national and regional governments, partner organizations, local communities, and Indigenous peoples in Bolivia and Brazil to solidify and expand protection of the Pantanal-Gran Chaco region’s extraordinary biodiversity, as well as to promote sustainable land uses that support the livelihoods of those who rely on these ecosystems. 

Roughly 30 million acres of intact Gran Chaco forest and associated ecosystems remain in Bolivia.⁵ Combined with those in northern Paraguay and northern Argentina, they form a continuous 90 million-acre swath of wildlands that have largely resisted deforestation.⁶ Additionally, over 42 million acres of the Pantanal lie in eastern Bolivia’s Santa Cruz Department and in two states in central-western Brazil: Mato Grosso and Mato Grosso do Sul.⁷

The Pantanal and Gran Chaco Wildlands at the Heart of South America

The region is among the world’s most ecologically diverse areas

The intact portions of the Gran Chaco and the adjacent Pantanal landscapes cover an area larger than California—more than 120 million acres of ecologically important wildlands in the Upper Paraguay River Basin.

Pantanal

	The Pantanal is the world’s largest tropical wetland, spanning more than 44 million acres and supporting substantial populations of jaguars, giant otters, marsh deer, and hyacinth macaws.
Approximately 80% of the Pantanal is in Brazil, with the rest in Bolivia and Paraguay—all contributing to the livelihoods of about 1.5 million people who depend on the economic opportunities that the area’s traditional cattle ranching, tourism, and fishing sectors provide.
	Nearly one-third of the area—a section roughly the size of Switzerland—was burned by wildfires in 2020 amid a severe drought caused by a lack of rainfall and a diminished supply of floodwater draining from several South American rivers into the vast inland delta.

Gran Chaco

The Gran Chaco, one of the world’s largest dry forests, is the second-largest South American forest ecoregion, after the Amazon. Covering more than 263 million acres, this area includes both intact and degraded or converted lands, and it also sustains thousands of animal species, such as jaguars, tapirs, and peccaries.
	The Gran Chaco spans Argentina, Bolivia, Brazil, and Paraguay, with a significant portion of the best-preserved areas located in Bolivia. The entire Gran Chaco ecoregion is home to about 9 million people. And, particularly in rural areas, a large share of the population is made up of Indigenous peoples such as the Guaraní, Ayoreo, Yshir, and Weenhayek peoples.
From 2000 to 2021, the region lost 27 million acres of native vegetation because of land-clearing for crop and livestock production—the equivalent of losing an area four times the size of Central Park every day.
Sources: Walfrido M. Tomas et al., Sustainability Agenda for the Pantanal Wetland: Perspectives on a Collaborative Interface for Science, Policy, and Decision-Making, 2019; The Nature Conservancy, Pantanal, March 18, 2024; World Wildlife Fund, Pantanal, March 1, 2024; Elizabeth Claire Alberts, The Pantanal Is Burning Again. Will It Be Another Devastating Year?, Sept. 16, 2021; The Nature Conservancy et al., Evaluación Ecorregional del Gran Chaco Americano, 2005; The Nature Conservancy, Gran Chaco: Protecting the Second-Largest Forest in South America, May 24, 2024; MapBiomas [Chaco], Gran Chaco, 22 Años de Cambios en la Cobertura y Uso del Suelo, 2022

Pew in Bolivia and Brazil

Over the next several years, Pew and its partners will help conserve the Upper Paraguay River Basin biomes while also supporting Indigenous peoples’ ongoing stewardship of these majestic and ecologically important lands.

Pew is helping its partners in Bolivia and Brazil to:

• Secure and improve public and private protected area management, based on the International Union for Conservation of Nature’s global standards, known as the Green List.
• Designate new protected areas to fill key gaps and maintain habitat connectivity.
• Support Indigenous territorial management to advance conservation and sustainable use.
• Promote the development and application of standards for sustainable ranchland management.
• Advance long-term financing mechanisms to ensure these conservation measures’ longevity.

Endnotes

1. “Infographics Show the Importance of the Pantanal and the Main Threats Faced by the Biome,” World Wildlife Fund, Nov. 11, 2015, https://www.wwf.org.br/?50183/Infographics-show-the-importance-of-the-Pantanal-and-the-main-threats-faced-by-the-biome.
2. “Gran Chaco: Protecting the Second-Largest Forest in South America,” The Nature Conservancy, accessed May 24, 2024, https://www.nature.org/en-us/about-us/where-we-work/latin-america/argentina/gran-chaco/.
3. Nestor I. Gasparri, Héctor R. Grau, and Jorgelina Gutiérrez Angonese, “Linkages Between Soybean and Neotropical Deforestation: Coupling and Transient Decoupling Dynamics in a Multi-Decadal Analysis,” Global Environmental Change 23, no. 6 (2013): 1605-14, https://doi.org/10.1016/j.gloenvcha.2013.09.007.
4. Fernanda Wenzel, Naira Hofmeister, and Pedro Papini, “Demand for Soy Puts Pressure on Pantanal, Brazil’s Largest Wild Wetland,” Mongabay, June 23, 2021, https://news.mongabay.com/2021/06/demand-for-soy-puts-pressure-on-pantanal-brazils-largest-wild-wetland/.
5. Robert Padilla and David Tecklin, “Ocupación de Bosque Intacto en Propuesta de Área Prioritaria de Conservación, en la Cuenca del Río Paraguay,” 2021.
6. Robert Padilla and David Tecklin, “Ocupación de Bosque Intacto.”
7. Walfrido M. Tomas et al., “Sustainability Agenda for the Pantanal Wetland: Perspectives on a Collaborative Interface for Science, Policy, and Decision-Making,” Tropical Conservation Science 12 (2019): https://doi.org/10.1177/1940082919872634.