Kid environmentalists have derailed a $900 million development in a popular Mexican resort town

A group of kids in Cancún, one of Mexico’s hottest resort towns, has stopped the razing of dozens of hectares of mangrove forest for a massive development—for now.

On Nov. 4, a judge granted the children’s request to permanently suspend the 69-hectare mixed-use project, but ruled that the children should pay a bond of 21 million pesos (about US$1.2 million) to offset developers’ losses. The group’s attorneys are trying to convince the court that the bond should not apply to minors.

The project, which was started by Mexico’s tourism development agency, has been in the works for more than two decades. Local environmentalists have been fighting it just as long.

But after bulldozers started leveling down trees and chasing crocodiles out of mangrove-covered land to make way for homes, shops, and a grandiose promenade this summer, many more Cancún residents jumped into action.

In September, 113 of their children filed a complaint asking a judge to halt the project’s construction, arguing that they have the constitutional right to a healthy environment.

“If we cut everything down then we’re going to die,” Ana, a four-year-old plaintiff, told Quartz. “Trees help us breathe.”

The tourism development agency did not immediately respond to requests for comment, but a spokesman told Mexican newspaper El Economista that canceling the project will result in the loss of some $900 million in investment (link in Spanish.)

The recent suit is the first filed in Mexico advocating for the collective rights of kids over corporate interests in order to protect the environment, said Carla Gil, the group’s lawyer, in an interview with Quartz. (Earlier this year, a group of children in the US filed a case using similar arguments to force the Obama administration to act on climate change.)

Antonella Vazquez, the mother of a plaintiff, says it’s important for children to raise their voices, even at the age of five, like her daughter did. For generations, Mexicans have had the defeatist attitude of “What for? Nothing is going to happen,” she tells Quartz.

Given the pace of development in Cancún, if her daughter doesn’t speak up, “there’s going to be nothing left for her,” she adds.

Mexico has more mangrove-covered surface than most countries, according to its own National Commission for the Knowledge and Use of Biodiversity. But over the past three decades, it’s lost 10% of it, data from the commission shows.

As Cancún and the nearby coast, known as the Mayan Riviera, become more popular among tourists, the dense, swampy forest that acts as a hurricane buffer is being replaced by hotels and resorts.

“For the Cancún community, protecting the mangroves is a matter of survival,” said Araceli Dominguez, an environmentalist with Grupo Gema, a local group. “It’s not just the romanticism of wanting to protect little plants.”

home our picks popular latest obsessions search