A coalition of more than 40 scientists is warning that a proposal to create a new artificial shipping channel through South America's Pantanal wetlands could lead to the "end of an entire biome." 

The 42 million-acre Pantanal — spread across Brazil, Bolivia and Paraguay — is the world's largest freshwater wetland, with thousands of birds, plant and fish species calling it home. The proposed project from the Brazilian government would dredge and restructure waterways at hundreds of sites along 435 miles of the Paraguay and Parana rivers, carving out space for barges to transport agricultural products from Brazil, Bolivia and Paraguay to Argentina and Uruguay, before exporting them to North America, Europe and Asia. 

But according to a paper from a group of scientists published in the Science of the Total Environment journal, the project could have disastrous consequences for the surrounding wetlands. Currently, the Pantanal gets filled with floodwaters like a large reservoir between October and March, which gradually drain out in the ensuing months, creating a delicate ecosystem of aquatic habitats and delivering crucial nutrients for plant and animal life. According to scientists, the new channel system would require crews to deepen the significantly deepen the upper portion of the Paraguay River, which would lower water levels, shrink the wetlands, and irrevocably disrupt the Pantanal's critical flood cycles. 

The paper also points out that shrinking the wetlands would dry the surrounding area out, making it more vulnerable to summer wildfires. The region has already gone through one of its worst ever fire seasons on record in 2024, with blazes having burnt nearly 3.7 million acres of the Brazilian Pantanal through early August. Even without the new channel project, the World Wildlife Fund predicts that the Pantanal's natural vegetation will likely disappear by 2050 at the current rate of deforestation in the area, with more than 12% of the wetland's forest cover having already been lost.