Editor's Note: (Call to Earth is a CNN initiative in partnership with Rolex. Erika Cuéllar is a biologist and conservationist, and a Rolex Award Laureate.)
(CNN) An arid region of open forests and grasslands spanning three countries and more than a quarter of a million square miles, this is Gran Chaco. It's the second-largest forest in South America after the Amazon, but has long been neglected, suffering from deforestation, agricultural expansion and the effects of climate change.
When Bolivian conservation biologist Erika Cuéllar first saw the vast expanse in 1997, she was overcome by an urge to restore it. "I am very attracted to arid lands. When I was young, I was angry that nobody cared about dry lands and everybody cared about tropical rainforest," she says.
Despite looking open and empty, the area is teeming with unique vegetation and wildlife, from jaguars and ocelots to piranhas and vipers. It's also home to nine million people, including several indigenous communities.
Cuéllar took an original approach to restoration, enlisting local people and giving them technical training to become "parabiologists" -- like paramedics, she says, but for nature. Her efforts have helped to create sustainable conservation in the region, outlawing the hunting of guanacos (an animal closely related to the llama and native to South America) and bringing the species back from the brink of extinction.
For Cuéllar, land restoration is an impossible task without the involvement and knowledge of local people. Her successful parabiologist model in Gran Chaco has inspired similar programs around the world. Today, she works as an assistant professor at Sultan Qaboos University in Oman, lecturing on biodiversity and conservation.
Through Call to Earth, CNN is reporting on the environmental challenges facing our planet, and understanding the solutions. Cuéllar will be guest editor as the series explores themes around land restoration and rewilding, lending her expertise and commissioning features on the subject.
CNN spoke to Cuéllar about her passion not just for conservation and natural species, but for people.
The following interview has been edited for length and clarity.
CNN: Your conservation work has been centered on the Bolivian region of Gran Chaco. What drew you to this area?
Erika Cuéllar: If you arrive for the first time in Gran Chaco, your first impression is that this is very dry and very empty. But what is incredible is all the hidden diversity, because after the first night sleeping there, you wake up and get out from your tent and you are surrounded by the footprints of many different species.
It's also the first example of a national park co-administered by indigenous people, which was very interesting and novel in South America. Very rapidly I understood the importance of working with (local) people because they have the knowledge. It was a learning process for me, but now my approach is always related to people, even if the long-term objective is conservation.
CNN: Why is it important to involve indigenous people in land restoration, and how did you do this?
Erika Cuéllar: Indigenous people have the knowledge, they have the connection and, at least in Bolivia, they use the natural resources for living -- hunting or fishing, for instance. So, you are dealing with an ecosystem that involves people, and this is sometimes missing in conservation projects. If we want to protect a place and we have a lot of people nearby, we don't need to bring people from outside.
CNN: It's been almost a decade since you left Gran Chaco to work in other areas -- what do you believe your legacy is?
Erika Cuéllar: The greatest achievement is that I see those people that were in my training program working as professionals now. They are working as guardians or park rangers and they are also advisors to their community.
I am so proud to see that, for example, last year two of the parabiologists I trained were involved in the creation of protected areas. Others have represented their people in front of the municipality and in front of the government.
They don't depend on me, and that is my achievement. They can articulate the problems, they can suggest solutions, and they can discuss others potential solutions they do or do not agree with.
CNN: You've been credited with saving the guanaco in the Gran Chaco region, helping to push through a ban on hunting, suggesting a breeding program, and coming up with a recovery plan for the species' grassland habitat. Why is it important to save them?
Erika Cuéllar: The guanaco is one of the two South American camels, except they don't have a hump. They are wild species and historically the guanaco was widely distributed in Bolivia from the highlands to the lowlands, but today the only known population that exists in the country is the Chacoan (from Gran Chaco) populations.
It was important to me to catch the attention of the international scientific community, because the guanaco is considered a least-concern species as it is everywhere in Argentina, but in Bolivia, it was going to extinction.
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With public awareness and almost 10 years of monitoring the population of guanacos and just fighting for it, working there, we saved the species from extinction. For me, that is a great happiness in my life.
CNN: What are the critical issues facing the planet right now, and how can land restoration help to protect it?
Erika Cuéllar: There are many critical issues. Of course, one of the most obvious is the accelerated rate of climate change. Another great problem now is the massive migration of people, which will affect natural areas.
I think we are very worried about the extinction of species and maybe we're not thinking enough about the extinction of knowledge. The knowledge of people who are really connected and understand the patterns inside ecosystems have been neglected and they are very important.
Conservation without people is just gardening, I always use the phrase. We are part of the system. I think we need more hands and more brains and more help if we really want to hurry and protect these areas. We need allies where the land we want to conserve is. The empowerment of local people is important.