As the evening sky turns violet, the animals of the Pantanal gather by the water. Capybaras swim in tight formation, roseate spoonbills add pink spots to the riverbanks, the rumble of a jaguar pulses from the forest.
This tropical wetland is the largest in the world, stretching across Brazil, Paraguay and Bolivia, and is home to some of the largest gatherings of animals in the world.
Now scientists say the survival of the entire biome is in danger.
“The Pantanal is like Noah’s Ark. It is home to animals that are disappearing… a place where those who are threatened with extinction can survive,” says Pierre Girard, a professor at the Federal University of Mato Grosso.
“That could change,” he says. “The Pantanal, as we know it, could soon cease to exist.”
The 170,000-square-kilometre (42-million-acre) wilderness is home to one of the most biologically rich environments in the world, with at least 380 species of fish, 580 species of birds and 2,272 different plants. It is one of the world’s most important refuges for jaguars and is home to a number of vulnerable and endangered species, including giant otters, giant armadillos and hyacinth macaws.
It seems like a high price to pay: destroying the Pantanal, a unique system to lower the price of grain
Prof Carolina J da Silva
There are plans to revitalize the Paraguay River, one of the Pantanal’s main arteries, and transform it into an industrial shipping route for crops such as soybeans and sugar.
Political proponents say the waterway would reduce the cost and time of exporting agricultural products to North America, Europe and Asia, but critics warn that its construction — which would require building new ports, possibly straightening bends and meanders and extensive dredging — would cause irreparable damage to wetlands and wildlife.
“It seems like a high price to pay: destroying the Pantanal, one of the unique systems in the world, to lower the price of grain,” says Carolina Joana da Silva, a professor at Mato Grosso State University. “It is a war – a war that risks dying out.”
In a communal workshop for fishermen in Cáceres, 64-year-old Elza Basto Pereira, the community head, says that building materials arrived along the river six months ago.
“Roads are being built for the planned ports and materials are being stacked along the river; they keep coming,” she says.
The threat of the development, known as the Hidrovia Paraguay-Paraná waterway, has plagued the Pantanal for decades. Previous iterations – which involved dredging and straightening river bends in hundreds of locations – were suspended by the Brazilian government in 2000 due to environmental concerns.
But the push to develop waterways through the wetland has continued. Now experts believe a new strategy is underway, one in which parts of the project are approved piecemeal.
“Politicians and companies are forcing it through in chunks,” says Girard.
Last year, the Brazilian government announced that the Paraguay River, which drains the wetland for six months and floods it the rest of the year, would be developed under its Growth Acceleration Program. The website states that the national project has “great potential to reduce transportation costs” and that “discussions are underway with society and local stakeholders.”
The government has announced an investment of 81 million reais [£11m] for dredging, clearing vegetation and modifying the signage of the navigable channel. Provisional permits were issued for the construction of two port facilities in Porto Esperança and Cáceres, which opponents say is the first step toward transforming the largest natural stretch of the Paraguay River into a man-made waterway.
Lourenço Pereira Leite, 54, sits with Basto Pereira in the fishing shed in Cáceres. They are part of the ribeirinhos (riverside community) that lives from sustainable fishing and small-scale agriculture.
“They are trying to deceive us,” says Pereira Leite. “When the waterway was first presented in the 1990s, its proponents said it would bring prosperity – it didn’t. Instead, it started destroying the environment.
“Now they come again, with the same words ‘progress, progress’, but we know that this will mean the end of our fisheries and our families.”
Often called the “water kingdom,” the Pantanal is made up of more than 1,200 rivers and streams, and its vast biodiversity depends on seasonal flooding patterns. Scientists fear that dredging and deepening will effectively create a “big drain,” disconnecting the Paraguay River from its floodplains and shrinking the wetland area.
Scientists warn that this could destroy aquatic habitats, fish populations and bird nesting areas, and subsequently affect other species throughout the food chain.
According to Dr. Angélica Vilas Boas da Frota, a local biologist, the black scissorbill, the neotropical cormorant, the Mato Grossomier bird and the white-cheeked spinetail are among the species most at risk. However, larger mammals, such as jaguars, could also be affected by the declining fish populations.
Wetlands are also of global importance to the climate. Despite covering only 5-8% of the Earth’s land surface, they are thought to store up to 30% of terrestrial carbon. The Pantanal is a critical carbon sink, but constant dredging – which would be necessary to allow ships to pass through, due to the sandy sediment along the riverbed – would lead to greenhouse gas emissions, further contributing to global warming.
The risk of forest fires could also increase, but such concerns are not being heard, scientists say. “Brazil sees the Amazon as its international environmental playing card,” Girard says, while the Pantanal remains forgotten.
Near Tucum, 55-year-old Edna Luiz Dias grills a freshly caught pacu fish. Her wooden house on stilts is surrounded by trees and native plants. “I don’t need a lot of money — just the fish, the birds, the fruit, the nature,” she says.
“But this waterway could take all that away. I can already feel the river changing.”
This part of the Pantanal, close to Cáceres, is still sparsely populated due to the deep bends of the rivers and the dense marshes. But in Porto Esperança the effects of the large ships on the river are already noticeable.
An existing port is now being used to transport iron. The mineral is leaving a thin layer of red dust on the land and trees of the fishing village. Eight indigenous communities live in the Pantanal, and at least the Guató reserve would be directly affected by making the river navigable, scientists say.
“The ships have already damaged the environment by spreading iron across the water, our soil and our plants,” said Natalina Silva Oliveira Mendez, 50. “Adding the new port and creating the Hidrovia will be a disaster.”
However, local businessmen say the waterway—which they hope will allow year-round transportation—will bring economic development and prosperity to the region. Adilson Reis, an engineer from Cáceres who is working as a consultant on the project, predicts it will be operational by 2026.
“As we develop, it is necessary to increase transport options. For years, the waterway has been paralyzed,” says the 75-year-old. “As someone who was born here, I want the city of Cáceres to grow. I think the waterway will bring prosperity.”
Related: ‘The Pantanal is National Heritage’: protecting the largest wetlands in the world
He agrees that the environment is a concern, but says certain conditions can be enforced – such as limiting the size of ships – to limit the risk.
In response to this article, Brazil’s Ministry of Ports and Airports said that the concerns raised about environmental damage were “opinions” without “scientific elements to support them,” and that a debate would be held for each project. The Ministry of Environment and Climate Change did not respond to requests for comment.
There is a consensus among the ribeirinhos that the Hidrovia will indeed go ahead, but they are not prepared to give up their age-old way of life.
“Society doesn’t want to listen to us, because then they can create whatever they want: dams, waterways, ports,” says Luiz Dias.
“But I want the world to know that we are here – and that I will stay and fight for my life and for the Pantanal.”