Erika Cuéllar

Conservation Biologist

Emerging Explorer

Picture of Erika Cuéllar

Photograph by Rolex Awards/Thierry Grobet

Erika Cuéllar works to protect the wild environment of South America’s Gran Chaco region by training local people as parabiologists armed with professional scientific conservation skills. She co-coordinates the Bolivian Committee for the Species Survival Commission of the IUCN, and is a 2012 recipient of the Rolex Award for Enterprise.

South America’s Gran Chaco region spans an exceptionally complex mix of habitats, climates, topography, and species. Equally complex: preserving it from the onslaught of uncontrolled development that could transform the landscape forever. Erika Cuéllar’s innovative solutions and sheer passion bring new hope to the wildlife and people of this imperiled wilderness jewel.

Cuéllar empowers those who live in the Gran Chaco to be hands-on stewards of conservation by training them as parabiologists. Communities nominate participants for the 800-hour course covering everything from basic biology, mathematics, and other sciences to producing maps, using computers and GPS, designing research projects, collecting data, and presenting results. Those who pass the final exam bring their professional skills into the forests, wetlands, and grasslands. They make census reports of birds and mammals, deploy and analyze data from camera traps and radio-tracking devices, create maps calculating species’ densities, and monitor changes in wildlife numbers.

Their training helps save human lives, too. “These areas are so far from any medical center, people often die of appendicitis or snake bites that could be treated,” Cuéllar explains. “We include classes in first aid that can make a real difference in these cases.”

Parabiologists also play a crucial role in sharing conservation information with their communities to guide decisions about managing land and wildlife. The Gran Chaco covers territory in Bolivia, Argentina, Paraguay, and a sliver of Brazil. Great swaths of that land and populations of species have been destroyed by unregulated cattle ranching, logging, farming, railway construction, sport hunting, and other threats often spearheaded by wealthy city dwellers.

Indigenous people in Cuéllar’s native Bolivia felt such strong connection to the wilderness that they convinced the government to create a 3.4-million-hectare protected area in 1997. “Thanks to them, a large portion of the Gran Chaco is still healthy, but in Paraguay and Argentina, it is far more fragmented,” she reports.

“These local people are so intelligent and capable, but many spend half the year in the city working for next to nothing. I want to give them the chance to be professionals, stay home with their families, and take care of their own territory. People who have earned a parabiologist certificate are trusted liaisons with the outside world and placed in charge of conservation projects,” says Cuéllar. “Four went on to become park rangers and another is dealing directly with the government about land projects in his area. Our program instills confidence and pride and proves the extraordinary value of their local knowledge.”

Cuéllar has made one iconic South American species the symbol for her efforts. In Bolivia, the guanaco, wild ancestor of the llama, has dwindled to only 200 animals scattered in three isolated populations. “I spotlight them as a central conservation objective, because it’s easy to see how endangered they have become. But they stand for the entire assemblage of creatures that depend on the Gran Chaco—jaguar, puma, eight species of armadillos, endemic wild pigs, a multitude of bird and reptile species, and many more.”

Her efforts helped outlaw hunting of guanaco, and today she explores repopulating genetically inbred and isolated herds through breeding with herds in Paraguay. She also experiments with ways to recover the guanaco’s grassland habitat, overrun by free-range cattle and invasive plants. She’s asking the local government municipality to create a protected reserve for guanaco, while at the same time creating new, environmentally sustainable ways for local people to earn income.

Now she faces her biggest challenge yet: saving the entire Gran Chaco region by extending grassroots efforts up through all levels of Bolivia’s government and beyond to create a multinational endeavor between Bolivia, Paraguay, and Argentina.

“I’m working to bring authorities and organizations across all three countries together to establish priorities, obtain a baseline on the current situation, agree on a common methodology, and expand our training program," Cuéllar says. "Governments need to provide a formal structure and officially recognize our education initiative if preservation projects are to succeed long term.

“I receive emails from people all over the world who want to apply our parabiologist approach to their regions. I’m so happy to think it can be a prototype," she says. "I truly believe it’s crucial to integrate people who live next to protected areas into the conservation process. It’s working!”


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