The Brazilian government wants to develop the upper 435 miles (700km) of the Paraguay River into the Paraguay-Paraná hidrovia (waterway). In 2022 and 2023, preliminary licences were issued for the construction of port facilities within the Pantanal.
Prof Karl M Wantzen, an ecologist from the University of Tours, and Unesco chair for river culture, said the wetland “is a real paradise on Earth. Nowhere else will you see so many hyacinth macaws, jaguars, swamp deer, anacondas, caymans, more than 300 fish species, 500 bird species, 2,500 species of water plants … All of that is at risk.”
In 2024, fires were the worst on record, with nearly 1.5m hectares (3.7m acres) burning across the Brazilian Pantanal by early August. Since 1985, the Pantanal has lost about 80% of its surface water – more than any other biome in Brazil. If the waterway goes ahead it is likely to further shrink the wetland, making it even more dry and vulnerable to wildfires such as those seen in 2020.
The upper section of the Paraguay River is sinuous and shallow. Making it navigable for 50-metre barges would mean extensive dredging, fixing of riverbanks and construction of ports. This would permanently alter the natural cycle of flooding and shrink the wetland area, researchers warned. Wantzen and Girard are two of more than 40 scientists who wrote a paper, published in the journal Science of the Total Environment, arguing that the waterway must not be expanded into the wetlands.
Wantzen, the lead author, said he and his colleagues published it because “I really want the world to know what’s happening. I wanted to gather people to spell out what the current situation is. It would be a senseless tragedy.”
“The Paraguay River flowing through the Pantanal is the last large riverscape in central South America that still has near-natural structure. It represents the biocultural heritage of the Brazilian people and the entire world,” researchers wrote.
Dredging this area would result in “severe degradation of the globally outstanding biological and cultural diversity of the Pantanal”, the paper warned. The wetland is also home to Indigenous peoples whose livelihoods would be threatened. The paper said railways would be a more reliable and less disruptive way to transport goods.
“Humanity is crazy, destroying everything it can and at high speed,” said Mario Friedlander, who works in wildlife observation tourism and photography in Mato Grosso. “The operation of the waterway in the Pantanal is yet another serious attack against a place that is powerful in nature, but completely unprotected.”
Responding to concerns raised by the scientists, the Brazilian Ministry for Ports and Airports said the paper contained “opinions” without “scientific elements to support them”.