The new docuseries “Patagonia: Life on the Edge of the World” explores one of the wildest places on Earth. The series airs Sundays at 9 p.m. ET/PT.

CNN  — 

At the northern tip of Patagonia’s desert coast in Argentina, the skies above El Cóndor are filled with shifting clouds of chatty, colorful parrots.

The mountain’s crumbling sandstone cliffs are home to the largest parrot colony in the world, containing 37,000 nests.

The burrowing parrots are so named because they tunnel into the sandy cliffsides to build their nests. These tunnels can be up to 9.8 feet (about 3 meters) deep.

With green feathers and white rings around their eyes, burrowing parrots stand out in this barren landscape overlooking the Atlantic Ocean. When the birds fly, bright blue and red feathers flash in the sky.

El Cóndor’s cliffs serve as a nesting ground for a species that once appeared all over South America, but the burrowing parrot population is now declining.

The parrots’ food source in the Argentine Monte is disappearing more quickly than the Amazon rainforest. This vulnerable region of desert grasslands and shrubs, which the parrots prefer, has suffered from deforestation.

The burrowing parrots have to fly three hours away from their nests just to find seeds and berries to bring back to their chicks within the cliff nests. Each year, the birds must travel farther to find something to eat, and it’s estimated the adults fly up to 164 miles (264 kilometers) per day, according to scientists at Justus Liebig University Giessen in Germany.

Moreover, threats from humans and growing tourism in the area are making life harder for the parrots.

A sky full of birds

Argentine director Kevin Zaouali, who made the first episode of the “Patagonia: Life on the Edge of the World” series that premieres Sunday on CNN, first saw the birds 10 years ago when he visited El Cóndor, entranced by “an entire sky covered by parrots.” Returning to the beach, he and his team had to remain patient, “waiting to see what the animals wanted to offer us.”

The parrots have distinctive white rings around their eyes and olive green plumage, with splashes of color underneath.

The film crew spent 20 days with the parrots, wanting to find special moments, Zaouali said. The team listened to the constant chatter of the highly social birds and observed other nuances of their behavior as well. Burrowing parrots are monogamous and mate for life – and they do everything together.

Zaouali said he was struck by “the way they look at each other and the way they touch each other. They’re always giving kisses to each other.”

Amid these glimpses of affection were moments fraught with tension.

Burrowing parrots are the prey of the peregrine falcon, the fastest bird on the planet. It can reach speeds of 240 miles per hour (386 kilometers per hour) when diving at its prey. At the site, the falcons moved so quickly that it was nearly impossible to capture their dives on camera.

Some fledgling chicks inside the nest grow curious as they wait for their parents to return from the feeding ground and fall to the bottom of the mountain if they lean out too far. Zaouali and his crew spent a day watching a chick painstakingly climb centimeter by centimeter back up to the nest after it fell out.

The sandstone cliffs pose other risks for the colony. The structures occasionally collapse, with massive blocks falling from the cliff face and killing the parrots dwelling inside. But the parrots return each year after spending winters in the north because they prefer the arid openness of the cliffs along the Atlantic coast.

Protecting parrots

The burrowing parrot is currently considered to be of “least concern,” according to the International Union for Conservation of Nature Red List of Threatened Species, but the species has been recognized as one that’s declining in population.

Due to their charm and color, burrowing parrots are exploited by the wildlife trade. They have also been hunted as pests who feed on crops. And because burrowing parrots are so picky about where they nest, they are easily disturbed if humans encroach on their space.

Burrowing parrots are incredibly loyal to one another and highly social.

Zaouali began filming and photographing animals 16 years ago, and he has already seen changes in the places he once visited as a child. He said he worries that “the land of adventure” could lose the largest parrot colony on Earth and other animals if protective measures aren’t taken for the vulnerable species that call Patagonia home.

“Patagonia is a very special place but also very, very fragile,” Zaouali said. “It’s unique and very wild, and while it seems very distant and pristine, if we don’t try to protect it, it will be like any other place full of pollution.”

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