From the top of the great pyramid of the ancient Maya city of Calakmul in the southern Yucatán Peninsula in Mexico, you can see all the way to Guatemala. Calakmul was once one of the largest and most powerful cities of the Maya world, but now it stands in ruins, hours from the nearest urban center and enveloped by the Calakmul Biosphere Reserve, one of the biggest swaths of unbroken tropical forest in the Americas.
It was early evening, and the black howler monkeys were waking up. From under the forest canopy came the guttural, trash-compactor roar of the loudest land animal in the world, one of many endangered species that live here, along with pumas, toucans, spider monkeys and coati-mundis. Perhaps most crucially, the jungle of Calakmul is home to the highest concentration of jaguars in Mexico.
The Maya, like other ancient civilizations of Mexico, worshiped the jaguar as a deity, believing that it ruled the underworld and could move between worlds at will. Across pre-Columbian cultures, jaguar images appear on masks, thrones, reliefs and sculptures. Ancient rulers and warriors adorned themselves with the animal’s skulls, skins, fangs and claws. For 3,000 years, no animal was more symbolically important.
In Mexico, an alliance of ecologists, nongovernmental organizations and local communities have embarked on an ambitious conservation project that has effectively pulled the species back from the brink of extinction — part of a broader mission to save the jungles of the Yucatán. In Mexico, the number of jaguars is now growing, increasing to 4,766 animals in 2018 from 4,025 in 2010, a promising sign that conservation strategies are working.
“The jaguar is an umbrella species, so by protecting the jaguar, you are protecting everything else,” said Gerardo Ceballos, an ecologist and conservationist who has been working with jaguars in the region for almost 25 years.
In 2005, Dr. Ceballos founded the Mexican Alliance for Jaguar Conservation, which is based in Mexico City, and has conducted some of the most comprehensive studies of the species to develop conservation strategies. The alliance’s work is more important than ever as a controversial new train line that will bisect the Calakmul Biosphere Reserve approaches completion. The 948-mile Tren Maya will begin in Chiapas and travel northeast toward Cancún, transporting tourists from beach resorts on the Caribbean coast to archaeological sites inland. Opponents of the project cite environmental damage and unlawful evictions, among other concerns; they gained a temporary injunction in 2020, but in late 2021, the Mexican government resumed construction.
Once news broke that the jaguar population was increasing, the government agreed to route the train line according to conservation needs, adding numerous wildlife passes. It also tentatively agreed to expand the Calakmul Biosphere Reserve beyond its 726,000 hectares, or nearly 1.8 million acres, connecting it with other reserves in the area. If the government stays true to its word, “we will end up with 1.3 million hectares of protected forest,” Dr. Ceballos said. “It will be one of the largest in the tropics of the world.”